LED tube lamp

ABSTRACT

The disclosure provides an LED tube lamp, comprising a tube, a terminal adapter circuit, a first rectifying circuit, a filtering circuit, an LED lighting module and an anti-flickering circuit. The tube has a first pin and a second pin for receiving an external driving signal. The terminal adapter circuit has two fuses respectively coupled to the first and second pins. The first rectifying circuit is coupled to the first and second pins for rectifying the external driving signal to generate a rectified signal. The filtering circuit is coupled to the first rectifying circuit for filtering the rectified signal to generate a filtered signal. The LED lighting module is coupled to the filtering circuit and the LED lighting module having a LED module, wherein the LED lighting module is configured to receive the filtered signal and generate a driving signal, and the LED module receives the driving signal and lights. The anti-flickering circuit is coupled between the filtering circuit and the LED lighting module, and is configured such that a current higher than a particular anti-flickering current flows through the anti-flickering circuit when a peak value of the filtered signal is higher than a minimum conduction voltage of the LED module.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a Continuation-in-Part application of U.S. patentapplication Ser. No. 14/865,387, filed Sep. 25, 2015, the contents ofwhich are incorporated herein by reference in their entirety, whichclaims priority to Chinese Patent Applications No. CN 201410507660.9filed on 2014 Sep. 28; CN 201410508899.8 filed on 2014 Sep. 28; CN201410623355.6 filed on 2014 Nov. 6; CN 201410734425.5 filed on 2014Dec. 5; CN 201510075925.7 filed on 2015 Feb. 12; CN 201510104823.3 filedon 2015 Mar. 10; CN 201510133689.x filed on 2015 Mar. 25; CN201510134586.5 filed on 2015 Mar. 26; CN 201510136796.8 filed on 2015Mar. 27; CN 201510155807.7 filed on 2015 Apr. 3; CN 201510173861.4 filedon 2015 Apr. 14; CN 201510193980.6 filed on 2015 Apr. 22; CN201510259151.3 filed on 2015 May 19; CN 201510268927.8 filed on 2015 May22; CN 201510284720.x filed on 2015 May 29; CN 201510315636.x filed on2015 Jun. 10; CN 201510338027.6 filed on 2015 Jun. 17; CN 201510372375.5filed on 2015 Jun. 26; CN 201510373492.3 filed on 2015 Jun. 26; CN201510378322.4 filed on 2015 Jun. 29; CN 201510391910.1 filed on 2015Jul. 2; CN 201510406595.5 filed on 2015 Jul. 10; CN 201510428680.1 filedon 2015 Jul. 20; CN 201510482944.1 filed on 2015 Aug. 7; CN201510483475.5 filed on 2015 Aug. 8; CN 201510486115.0 filed on 2015Aug. 8; CN 201510555543.4 filed on 2015 Sep. 2; CN 201510557717.0 filedon 2015 Sep. 6; and CN 201510595173.7 filed on 2015 Sep. 18, thedisclosures of which are incorporated herein in their entirety byreference. This application also claims priority to Chinese PatentApplications No. CN 201510324394.0 filed on 2015 Jun. 12; CN201510448220.5 filed on 2015 Jul. 27; CN 201510499512.1 filed on 2015Aug. 14; CN 201510645134.3 filed on 2015 Oct. 8; and CN 201510716899.1filed on 2015 Oct. 29, the disclosures of which are incorporated hereinin their entirety by reference.

FIELD

The present disclosure relates to an LED tube lamp, and moreparticularly to an LED tube lamp and its components including ananti-flickering circuit.

BACKGROUND

Light emitting diode (LED) lighting technology is rapidly developing toreplace traditional incandescent and fluorescent lighting. LED tubelamps are mercury-free in comparison with fluorescent tube lamps thatneed to be filled with inert gas and mercury. Thus, it is not surprisingthat LED tube lamps are becoming a highly desired illumination optionamong different available lighting systems used in homes and workplaces,which used to be dominated by traditional lighting options such ascompact fluorescent light bulbs (CFLs) and fluorescent tube lamps.Benefits of LED tube lamps include improved durability and longevity andfar less energy consumption; therefore, when taking into account allfactors, they would typically be considered as a cost effective lightingoption.

Typical LED tube lamps have a lamp tube, a circuit board disposed insidethe lamp tube with light sources being mounted on the circuit board, andend caps accompanying a power supply provided at two ends of the lamptube with the electricity from the power supply transmitting to thelight sources through the circuit board.

The available electronic ballasts are mainly classified into two typesof instant start electronic ballast and pre-heat start electronicballast. The electronic ballast has a resonant circuit, which isdesigned to match a load characteristic of a fluorescent lamp to providean appropriate ignition process for igniting the lamp. The loadcharacteristic of the fluorescent lamp is capacitive before the lamp isignited and is resistive after the lamp is ignited. The LED is anon-linear load, having a completely different load characteristic.Therefore, the LED tube lamp affects the resonance of the resonantcircuit and tends to cause compatible problems. In general, the pre-heatelectronic ballast detects the filament of the lamp during ignitionprocess. However, the conventional LED driving circuit can not supplythe filament detection and so can not light with the pre-heat electronicballast. In addition, the electronic ballast is effectively a currentsource, and it easily results in the problems of over current, overvoltage, under current and the under voltage when being used to be apower supply of the LED tube lamp. The LED tube lamp may not providestable lighting and even the electrical device therein may be damaged.Moreover, a transient flicker may appear after the user turns off thepower, which may cause user discomfort.

Accordingly, the present disclosure and its embodiments are hereinprovided.

SUMMARY

It's specially noted that the present disclosure may actually includeone or more inventions claimed currently or not yet claimed, and foravoiding confusion due to unnecessarily distinguishing between thosepossible inventions at the stage of preparing the specification, thepossible plurality of inventions herein may be collectively referred toas “the (present) invention” herein.

Various embodiments are summarized in this section, and are describedwith respect to the “present invention,” which terminology is used todescribe certain presently disclosed embodiments, whether claimed ornot, and is not necessarily an exhaustive description of all possibleembodiments, but rather is merely a summary of certain embodiments.Certain of the embodiments described below as various aspects of the“present invention” can be combined in different manners to form an LEDtube lamp or a portion thereof.

The present invention provides a novel LED tube lamp, and aspectsthereof.

In one embodiment, an LED tube lamp comprises a tube, a terminal adaptercircuit, a first rectifying circuit, a filtering circuit, an LEDlighting module and an anti-flickering circuit. The tube has a first pinand a second pin for receiving an external driving signal. The terminaladapter circuit has two fuses respectively coupled to the first andsecond pins. The first rectifying circuit is coupled to the first andsecond pins for rectifying the external driving signal to generate arectified signal. The filtering circuit is coupled to the firstrectifying circuit for filtering the rectified signal to generate afiltered signal. The LED lighting module is coupled to the filteringcircuit and the LED lighting module having an LED module, wherein theLED lighting module is configured to receive the filtered signal andgenerate a driving signal, and the LED module receives the drivingsignal and emits light. The anti-flickering circuit is coupled betweenthe filtering circuit and the LED lighting module, and is configuredsuch that a current higher than a particular anti-flickering currentflows through the anti-flickering circuit when a peak value of thefiltered signal is higher than a minimum conduction voltage of the LEDmodule.

The anti-flickering circuit may comprise at least one resistor.

The rectifying circuit may be a full-wave rectifying circuit.

In one embodiment, an LED tube lamp comprises an over voltage protectioncircuit coupled to a first filtering output terminal and a second outputterminal of the filtering circuit to detect the filtered signal forclamping a voltage level of the filtered signal when the voltage levelof the filtered signal is higher than a particular over voltage value.

The over voltage protection circuit may comprise a voltage clampingdiode.

A frequency of the external driving signal may be in the range of 20k-50 k Hz.

The LED module may comprise at least two LED units, and each LED unitmay comprise at least two LEDs.

The first and second pins may be respectively disposed at two oppositeend caps of the LED tube lamp to form a single pin at each end of LEDtube lamp.

In one embodiment, an LED tube lamp comprises a second rectifyingcircuit coupled to a third pin and a fourth pin for rectifying theexternal driving signal concurrently with the first rectifying circuit.

The first and second pins may be disposed on one end cap of the LED tubelamp and the third and fourth pins are disposed on the other cap endthereof.

In one embodiment, an LED tube lamp comprises two filament-simulatingcircuits, wherein one filament-simulating circuit hasfilament-simulating terminals coupled to the first and second pins, andthe other filament-simulating circuit has filament-simulating terminalscoupled to the third and fourth pins.

In one embodiment, an LED tube lamp comprises a tube, a first rectifyingcircuit, a filtering circuit, an LED lighting module, an anti-flickeringcircuit and an over voltage protection circuit. The tube has a first pinand a second pin for receiving an external driving signal. The firstrectifying circuit is coupled to the first and second pins forrectifying the external driving signal to generate a rectified signal.The filtering circuit is coupled to the first rectifying circuit forfiltering the rectified signal to generate a filtered signal. The LEDlighting module is coupled to the filtering circuit and the LED lightingmodule has a LED module, wherein the LED lighting module is configuredto receive the filtered signal and generate a driving signal, and theLED module receives the driving signal and emits light. Theanti-flickering circuit is coupled between the filtering circuit and theLED lighting module, and a current higher than a set, particularanti-flickering current flows through the anti-flickering circuit when apeak value of the filtered signal is higher than a minimum conductionvoltage of the LED module. The over voltage protection circuit iscoupled to a first filtering output terminal and a second outputterminal of the filtering circuit to detect the filtered signal forclamping a voltage level of the filtered signal when the voltage levelof the filtered signal is higher than a set, particular over voltagevalue.

The anti-flickering circuit may comprise at least one resistor.

The rectifying circuit may be a full-wave rectifying circuit.

The over voltage protection circuit may comprise a voltage clampingdiode.

A frequency of the external driving signal may be in the range of 20k-50 k Hz.

The LED module may comprise at least two LED units, and each LED unitmay comprise at least two LEDs.

In one embodiment, an LED tube lamp comprises a second rectifyingcircuit coupled to a third pin and a fourth pin for rectifying theexternal driving signal concurrently with the first rectifying circuit.

In one embodiment, the first and second pins are disposed on one end capof the LED tube lamp and the third and fourth pins are disposed on theother cap end thereof.

In one embodiment, an LED tube lamp comprises two filament-simulatingcircuits, wherein one filament-simulating circuit hasfilament-simulating terminals coupled to the first and second pins, andthe other filament-simulating circuit has filament-simulating terminalscoupled to the third and fourth pins.

In one embodiment an LED tube lamp comprises two fuses, wherein one fuseis coupled to the first pin and the other fuse is coupled to the secondpin.

The first and second pins may be respectively disposed at two oppositeend caps of the LED tube lamp to form a single pin at each end of LEDtube lamp.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a perspective view schematically illustrating an LED tube lampaccording to one embodiment of the present invention;

FIG. 1A is a perspective view schematically illustrating the differentsized end caps of an LED tube lamp according to another embodiment ofthe present invention to illustrate;

FIG. 2 is an exploded view schematically illustrating the LED tube lampshown in FIG. 1;

FIG. 3 is a perspective view schematically illustrating front and top ofan end cap of the LED tube lamp according to one embodiment of thepresent invention;

FIG. 4 is a plane cross-sectional view schematically illustrating insidestructure of the glass tube of the LED tube lamp according to oneembodiment of the present invention, wherein two reflective films arerespectively adjacent to two sides of the LED light strip along thecircumferential direction of the glass tube;

FIG. 5 is a plane cross-sectional view schematically illustrating insidestructure of the glass tube of the LED tube lamp according to anotherembodiment of the present invention, wherein only a reflective film isdisposed on one side of the LED light strip along the circumferentialdirection of the glass tube;

FIG. 6 is a plane cross-sectional view schematically illustrating insidestructure of the glass tube of the LED tube lamp according to stillanother embodiment of the present invention, wherein the reflective filmis under the LED light strip and extends at both sides along thecircumferential direction of the glass tube;

FIG. 7 is a plane cross-sectional view schematically illustrating insidestructure of the glass tube of the LED tube lamp according to yetanother embodiment of the present invention, wherein the reflective filmis under the LED light strip and extends at only one side along thecircumferential direction of the glass tube;

FIG. 8 is a plane cross-sectional view schematically illustrating insidestructure of the glass tube of the LED tube lamp according to still yetanother embodiment of the present invention, wherein two reflectivefilms are respectively adjacent to two sides of the LED light strip andextend along the circumferential direction of the glass tube;

FIG. 9 is a plane sectional view schematically illustrating the LEDlight strip is a bendable circuit sheet with ends thereof passing acrossthe glass tube of the LED tube lamp to be solder bonded to the outputterminals of the power supply according to one embodiment of the presentinvention;

FIG. 10 is a plane cross-sectional view schematically illustrating abi-layered structure of the bendable circuit sheet of the LED lightstrip of the LED tube lamp according to an embodiment of the presentinvention;

FIG. 11 is a perspective view schematically illustrating the solderingpad of the bendable circuit sheet of the LED light strip for solderingconnection with the printed circuit board of the power supply of the LEDtube lamp according to one embodiment of the present invention;

FIG. 12 is a plane view schematically illustrating the arrangement ofthe soldering pads of the bendable circuit sheet of the LED light stripof the LED tube lamp according to one embodiment of the presentinvention;

FIG. 13 is a plane view schematically illustrating a row of threesoldering pads of the bendable circuit sheet of the LED light strip ofthe LED tube lamp according to another embodiment of the presentinvention;

FIG. 14 is a plane view schematically illustrating two rows of solderingpads of the bendable circuit sheet of the LED light strip of the LEDtube lamp according to still another embodiment of the presentinvention;

FIG. 15 is a plane view schematically illustrating a row of foursoldering pads of the bendable circuit sheet of the LED light strip ofthe LED tube lamp according to yet another embodiment of the presentinvention;

FIG. 16 is a plane view schematically illustrating two rows of twosoldering pads of the bendable circuit sheet of the LED light strip ofthe LED tube lamp according to yet still another embodiment of thepresent invention;

FIG. 17 is a plane view schematically illustrating through holes areformed on the soldering pads of the bendable circuit sheet of the LEDlight strip of the LED tube lamp according to one embodiment of thepresent invention;

FIG. 18 is a plane cross-sectional view schematically illustratingsoldering bonding process utilizing the soldering pads of the bendablecircuit sheet of the LED light strip of FIG. 17 taken from side view andthe printed circuit board of the power supply according to oneembodiment of the present invention;

FIG. 19 is a plane cross-sectional view schematically illustratingsoldering bonding process utilizing the soldering pads of the bendablecircuit sheet of the LED light strip of FIG. 17 taken from a side viewand the printed circuit board of the power supply according to anotherembodiment of the present invention, wherein the through hole of thesoldering pads is near the edge of the bendable circuit sheet;

FIG. 20 is a plane view schematically illustrating notches formed on thesoldering pads of the bendable circuit sheet of the LED light strip ofthe LED tube lamp according to one embodiment of the present invention;

FIG. 21 is a plane cross-sectional view of FIG. 20 taken along a lineA-A′;

FIG. 22 is a perspective view schematically illustrating a circuit boardassembly composed of the bendable circuit sheet of the LED light stripand the printed circuit board of the power supply according to anotherembodiment of the present invention;

FIG. 23 is a perspective view schematically illustrating anotherarrangement of the circuit board assembly of FIG. 22;

FIG. 24 is a perspective view schematically illustrating an LED leadframe for the LED light sources of the LED tube lamp according to oneembodiment of the present invention;

FIG. 25 is a perspective view schematically illustrating a power supplyof the LED tube lamp according to one embodiment of the presentinvention;

FIGS. 26A to 26F are views schematically illustrating various end capshaving safety switches according to embodiments of the presentinvention;

FIG. 27 is a plane view schematically illustrating a LED tube lamp withend caps having safety switches according to one embodiment of thepresent invention;

FIG. 28A is a block diagram of an exemplary power supply module 250 inan LED tube lamp according to some embodiments of the present invention;

FIG. 28B is a block diagram of an exemplary power supply module 250 inan LED tube lamp according to some embodiments of the present invention;

FIG. 28C is a block diagram of an exemplary LED lamp according to someembodiments of the present invention;

FIG. 28D is a block diagram of an exemplary power supply module 250 inan LED tube lamp according to some embodiments of the present invention;

FIG. 28E is a block diagram of an LED lamp according to some embodimentsof the present invention;

FIG. 29A is a schematic diagram of a rectifying circuit according tosome embodiments of the present invention;

FIG. 29B is a schematic diagram of a rectifying circuit according tosome embodiments of the present invention;

FIG. 29C is a schematic diagram of a rectifying circuit according tosome embodiments of the present invention;

FIG. 29D is a schematic diagram of a rectifying circuit according tosome embodiments of the present invention;

FIG. 30A is a schematic diagram of a terminal adapter circuit accordingto some embodiments of the present invention;

FIG. 30B is a schematic diagram of a terminal adapter circuit accordingto some embodiments of the present invention;

FIG. 30C is a schematic diagram of a terminal adapter circuit accordingto some embodiments of the present invention;

FIG. 30D is a schematic diagram of a terminal adapter circuit accordingto some embodiments of the present invention;

FIG. 31A is a schematic diagram of an LED module according to someembodiments of the present invention;

FIG. 31B is a schematic diagram of an LED module according to someembodiments of the present invention;

FIG. 31C is a plan view of a circuit layout of the LED module accordingto some embodiments of the present invention;

FIG. 31D is a plan view of a circuit layout of the LED module accordingto some embodiments of the present invention;

FIG. 31E is a plan view of a circuit layout of the LED module accordingto some embodiments of the present invention;

FIG. 32A is a block diagram of an exemplary power supply module in anLED lamp according to some embodiments of the present invention;

FIG. 32B is a schematic diagram of an anti-flickering circuit accordingto some embodiments of the present invention;

FIG. 33A is a block diagram of an exemplary power supply module in anLED tube lamp according to some embodiments of the present invention;

FIG. 33B is a schematic diagram of a filament-simulating circuitaccording to some embodiments of the present invention;

FIG. 33C is a schematic block diagram including a filament-simulatingcircuit according to some embodiments of the present invention;

FIG. 33D is a schematic block diagram including a filament-simulatingcircuit according to some embodiments of the present invention;

FIG. 33E is a schematic diagram of a filament-simulating circuitaccording to some embodiments of the present invention;

FIG. 33F is a schematic block diagram including a filament-simulatingcircuit according to some embodiments of the present invention;

FIG. 34A is a block diagram of an exemplary power supply module in anLED tube lamp according to some embodiments of the present invention;and

FIG. 34B is a schematic diagram of an over-voltage protection (OVP)circuit according to an embodiment of the present invention.

DETAILED DESCRIPTION

The present disclosure provides a novel LED tube lamp based on the glassmade tube to address some of the shortcomings described above. Thepresent disclosure will now be described in the following embodimentswith reference to the drawings. The following descriptions of variousembodiments of this invention are presented herein for purpose ofillustration and giving examples only. It is not intended to beexhaustive or to be limited to the precise form disclosed. These exampleembodiments are just that—examples—and many implementations andvariations are possible that do not require the details provided herein.It should also be emphasized that the disclosure provides details ofalternative examples, but such listing of alternatives is notexhaustive. Furthermore, any consistency of detail between variousexamples should not be interpreted as requiring such detail—it isimpracticable to list every possible variation for every featuredescribed herein. The language of the claims should be referenced indetermining the requirements of the invention.

In the drawings, the size and relative sizes of components may beexaggerated for clarity. Like numbers refer to like elements throughout.

The terminology used herein is for the purpose of describing particularembodiments only and is not intended to be limiting of the invention. Asused herein, the singular forms “a”, “an” and “the” are intended toinclude the plural forms as well, unless the context clearly indicatesotherwise. As used herein, the term “and/or” includes any and allcombinations of one or more of the associated listed items and may beabbreviated as “/”.

It will be understood that, although the terms first, second, third etc.may be used herein to describe various elements, components, regions,layers, or steps, these elements, components, regions, layers, and/orsteps should not be limited by these terms. Unless the context indicatesotherwise, these terms are only used to distinguish one element,component, region, layer, or step from another element, component,region, or step, for example as a naming convention. Thus, a firstelement, component, region, layer, or step discussed below in onesection of the specification could be termed a second element,component, region, layer, or step in another section of thespecification or in the claims without departing from the teachings ofthe present invention. In addition, in certain cases, even if a term isnot described using “first,” “second,” etc., in the specification, itmay still be referred to as “first” or “second” in a claim in order todistinguish different claimed elements from each other.

It will be further understood that the terms “comprises” and/or“comprising,” or “includes” and/or “including” when used in thisspecification, specify the presence of stated features, regions,integers, steps, operations, elements, and/or components, but do notpreclude the presence or addition of one or more other features,regions, integers, steps, operations, elements, components, and/orgroups thereof.

It will be understood that when an element is referred to as being“connected” or “coupled” to or “on” another element, it can be directlyconnected or coupled to or on the other element or intervening elementsmay be present. In contrast, when an element is referred to as being“directly connected” or “directly coupled” to another element, or as“contacting” another element, there are no intervening elements present.Other words used to describe the relationship between elements should beinterpreted in a like fashion (e.g., “between” versus “directlybetween,” “adjacent” versus “directly adjacent,” etc.).

Embodiments described herein will be described referring to plan viewsand/or cross-sectional views by way of ideal schematic views.Accordingly, the exemplary views may be modified depending onmanufacturing technologies and/or tolerances. Therefore, the disclosedembodiments are not limited to those shown in the views, but includemodifications in configuration formed on the basis of manufacturingprocesses. Therefore, regions exemplified in figures may have schematicproperties, and shapes of regions shown in figures may exemplifyspecific shapes of regions of elements to which aspects of the inventionare not limited.

Spatially relative terms, such as “beneath,” “below,” “lower,” “above,”“upper” and the like, may be used herein for ease of description todescribe one element's or feature's relationship to another element(s)or feature(s) as illustrated in the figures. It will be understood thatthe spatially relative terms are intended to encompass differentorientations of the device in use or operation in addition to theorientation depicted in the figures. For example, if the device in thefigures is turned over, elements described as “below” or “beneath” otherelements or features would then be oriented “above” the other elementsor features. Thus, the term “below” can encompass both an orientation ofabove and below. The device may be otherwise oriented (rotated 90degrees or at other orientations) and the spatially relative descriptorsused herein interpreted accordingly.

Terms such as “same,” “equal,” “planar,” or “coplanar,” as used hereinwhen referring to orientation, layout, location, shapes, sizes, amounts,or other measures do not necessarily mean an exactly identicalorientation, layout, location, shape, size, amount, or other measure,but are intended to encompass nearly identical orientation, layout,location, shapes, sizes, amounts, or other measures within acceptablevariations that may occur, for example, due to manufacturing processes.The term “substantially” may be used herein to reflect this meaning.

Terms such as “about” or “approximately” may reflect sizes,orientations, or layouts that vary only in a small relative manner,and/or in a way that does not significantly alter the operation,functionality, or structure of certain elements. For example, a rangefrom “about 0.1 to about 1” may encompass a range such as a 0%-5%deviation around 0.1 and a 0% to 5% deviation around 1, especially ifsuch deviation maintains the same effect as the listed range.

Unless otherwise defined, all terms (including technical and scientificterms) used herein have the same meaning as commonly understood by oneof ordinary skill in the art to which this disclosure belongs. It willbe further understood that terms, such as those defined in commonly useddictionaries, should be interpreted as having a meaning that isconsistent with their meaning in the context of the relevant art and/orthe present application, and will not be interpreted in an idealized oroverly formal sense unless expressly so defined herein.

As used herein, items described as being “electrically connected” areconfigured such that an electrical signal can be passed from one item tothe other. Therefore, a passive electrically conductive component (e.g.,a wire, pad, internal electrical line, etc.) physically connected to apassive electrically insulative component (e.g., a prepreg layer of aprinted circuit board, an electrically insulative adhesive connectingtwo devices, an electrically insulative underfill or mold layer, etc.)is not electrically connected to that component. Moreover, items thatare “directly electrically connected,” to each other are electricallyconnected through one or more passive elements, such as, for example,wires, pads, internal electrical lines, resistors, etc. As such,directly electrically connected components do not include componentselectrically connected through active elements, such as transistors ordiodes.

Components described as thermally connected or in thermal communicationare arranged such that heat will follow a path between the components toallow the heat to transfer from the first component to the secondcomponent. Simply because two components are part of the same device orboard does not make them thermally connected. In general, componentswhich are heat-conductive and directly connected to otherheat-conductive or heat-generating components (or connected to thosecomponents through intermediate heat-conductive components or in suchclose proximity as to permit a substantial transfer of heat) will bedescribed as thermally connected to those components, or in thermalcommunication with those components. On the contrary, two componentswith heat-insulative materials therebetween, which materialssignificantly prevent heat transfer between the two components, or onlyallow for incidental heat transfer, are not described as thermallyconnected or in thermal communication with each other. The terms“heat-conductive” or “thermally-conductive” do not apply to any materialthat provides incidental heat conduction, but are intended to refer tomaterials that are typically known as good heat conductors or known tohave utility for transferring heat, or components having similar heatconducting properties as those materials.

Referring to FIGS. 1 and 2, an LED tube lamp of one embodiment of thepresent invention includes a glass tube 1, an LED light strip 2 disposedinside the glass tube 1, and two end caps 3 respectively disposed at twoends of the glass tube 1. The sizes of the two end caps 3 may be same ordifferent. Referring to FIG. 1A, the size of one end cap may in someembodiments be about 30% to about 80% times the size of the other endcap. In one embodiment, the end cap is wholly made of a plasticmaterial, and in one embodiment, the end cap is made by integralmolding. In one embodiment, the end caps are made of a transparentplastic material and/or a thermal conductive plastic material.

Furthermore, in certain embodiments, the glass tube and the end cap aresecured by a highly thermal conductive silicone gel, for example, with athermal conductivity not less than 0.7 w/m·k. For example, in oneembodiment the thermal conductivity of the highly thermal conductivesilicone gel is not less than 2 w/m·k. In one embodiment, the highlythermal conducive silicone gel is of high viscosity, and the end cap andthe end of the glass tube could be secured by using the highly thermalconductive silicone gel and therefore can be qualified in a torque testof 1.5 to 5 newton-meters (Nt-m) and/or in a bending test of 5 to 10newton-meters (Nt-m).

In one embodiment, the glass tube could be covered by a heat shrinksleeve (not shown) to make the glass tube electrically insulated. Forexample, the thickness range of the heat shrink sleeve may be 20 μm-200μm, and in some embodiments 50 μm-100 μm.

In some embodiments, the inner surface of the glass tube could be formedwith a rough surface while the outer surface of the glass tube remainsglossy. For example, the inner surface may be rougher than the outersurface. For example, the roughness Ra of the inner surface may be from0.1 to 40 μm, and in some embodiments, from 1 to 20 μm.

In some embodiments, controlled roughness of the surface is obtainedmechanically by a cutter grinding against a workpiece, deformation on asurface of a workpiece being cut off, or high frequency vibration in themanufacturing system. Alternatively, roughness may be obtainedchemically by etching a surface. Depending on the luminous effect theglass tube is designed to produce, a suitable combination of amplitudeand frequency of a roughened surface is provided by a matchingcombination of workpiece and finishing technique.

In some embodiments, the LED tube lamp is configured to reduce internalreflectance by applying a layer of anti-reflection coating to an innersurface of the glass tube. The coating has an upper boundary, whichdivides the inner surface of the glass tube and the anti-reflectioncoating, and a lower boundary, which divides the anti-reflection coatingand the air in the glass tube. Light waves reflected by the upper andlower boundaries of the coating interfere with one another to reducereflectance. The coating is made from a material with a refractive indexof a square root of the refractive index of the glass tube by vacuumdeposition. Tolerance of the refractive index is ±20%. The thickness ofthe coating is chosen to produce destructive interference in the lightreflected from the interfaces and constructive interference in thecorresponding transmitted light. In some embodiments, reflectance isfurther reduced by using alternating layers of a low-index coating and ahigher-index coating. The multi-layer structure is designed to, whensetting parameters such as combination and permutation of layers,thickness of a layer, refractive index of the material, give lowreflectivity over a broad band that covers at least 60%, or preferably,80% of the wavelength range beaming from the LED light source 202. Insome embodiments, three successive layers of anti-reflection coatingsare applied to an inner surface of the glass tube 1 to obtain lowreflectivity over a wide range of frequencies. The thicknesses of thecoatings are chosen to give the coatings optical depths of,respectively, one half, and one quarter of the wavelength range comingfrom the LED light source 202. Dimensional tolerance for the thicknessof the coating is set at ±20%.

In some embodiments, the terminal part of the glass tube to be incontact with (e.g., to touch) the end cap includes a protrusion regionwhich could be formed to rise inwardly or outwardly. Furthermore, theouter surface of the protrusion region may be rougher than the outersurface of the glass tube. These protrusion regions help to contributelarger contact surface areas for the adhesives between the glass tubeand the end caps such that the connection between the end caps and theglass tube become more secure.

Referring to FIGS. 2, and 3, in one embodiment, the end cap 3 may haveopenings 304 to dissipate heat generated by the power supply modulesinside the end cap 3 so as to prevent a high temperature conditioninside the end cap 3 that might reduce reliability. In some embodiments,the openings are in a curved shape such as a shape of arc; especially inshape of three arcs with different size. In one embodiment, the openingsare in a shape of three arcs with gradually varying size. The openingson the end cap 3 can be in any one of the above-mentioned shape or anycombination thereof.

In other embodiments, the end cap 3 is provided with a socket (notshown) for installing the power supply module.

Referring to FIG. 4, in one embodiment, the glass tube 1 further has adiffusion film 13 coated and bonded to the inner wall thereof so thatthe light outputted or emitted from the LED light sources 202 isdiffused by the diffusion film 13 and then pass through the glass tube1. The diffusion film 13 can be in form of various types, such as acoating onto the inner wall or outer wall of the glass tube 1, or adiffusion coating layer (not shown) coated at the surface of each LEDlight source 202, or a separate membrane covering the LED light source202.

Referring again to FIG. 4, when the diffusion film 13 is in form of asheet, it covers but is not in contact with the LED light sources 202.The diffusion film 13 in form of a sheet is usually called an opticaldiffusion sheet or board, usually a composite made of mixing diffusionparticles into polystyrene (PS), polymethyl methacrylate (PMMA),polyethylene terephthalate (PET), and/or polycarbonate (PC), and/or anycombination thereof. The light passing through such composite isdiffused to expand in a wide range of space such as a light emitted froma plane source, and therefore makes the brightness of the LED tube lampuniform.

In alternative embodiments, the diffusion film 13 is in form of anoptical diffusion coating, which is composed of any one of calciumcarbonate, halogen calcium phosphate and aluminum oxide, or anycombination thereof. When the optical diffusion coating is made from acalcium carbonate with suitable solution, an excellent light diffusioneffect and transmittance to exceed 90% can be obtained.

In certain embodiments, the composition of the diffusion film 13 in formof the optical diffusion coating includes calcium carbonate, strontiumphosphate (e.g., CMS-5000, white powder), thickener, and a ceramicactivated carbon (e.g., ceramic activated carbon SW-C, which is acolorless liquid). Specifically, in some embodiments, such an opticaldiffusion coating on the inner circumferential surface of the glass tubehas an average thickness ranging between about 20 to about 30 μm. Alight transmittance of the diffusion film 13 using this opticaldiffusion coating is about 90%. Generally speaking, the lighttransmittance of the diffusion film 13 ranges from 85% to 96%. Inaddition, this diffusion film 13 can also provide electrical isolationfor reducing risk of electric shock to a user upon breakage of the glasstube 1. Furthermore, the diffusion film 13 provides an improvedillumination distribution uniformity of the light outputted by the LEDlight sources 202 such that the light can illuminate the back of thelight sources 202 and the side edges of the bendable circuit sheet so asto avoid the formation of dark regions inside the glass tube 1 andimprove the illumination comfort. In another possible embodiment, thelight transmittance of the diffusion film can be 92% to 94% while thethickness ranges from about 200 to about 300 μm.

In another embodiment, the optical diffusion coating can also be made ofa mixture including calcium carbonate-based substance, some reflectivesubstances like strontium phosphate or barium sulfate, a thickeningagent, ceramic activated carbon, and deionized water. The mixture iscoated on the inner circumferential surface of the glass tube and has anaverage thickness ranging between about 20 to about 30 μm. In view ofthe diffusion phenomena in microscopic terms, light is reflected byparticles. The particle size of the reflective substance such asstrontium phosphate or barium sulfate will be much larger than theparticle size of the calcium carbonate. Therefore, adding a small amountof reflective substance in the optical diffusion coating can effectivelyincrease the diffusion effect of light.

In other embodiments, halogen calcium phosphate or aluminum oxide canalso serve as the main material for forming the diffusion film 13. Theparticle size of the calcium carbonate is about 2 to 4 μm, while theparticle size of the halogen calcium phosphate and aluminum oxide areabout 4 to 6 μm and 1 to 2 μm, respectively. In one embodiment, when thelight transmittance is desired to be 85% to 92%, the average thicknessfor the optical diffusion coating mainly having the calcium carbonate isabout 20 to about 30 μm, while the average thickness for the opticaldiffusion coating mainly having the halogen calcium phosphate may beabout 25 to about 35 μm, and the average thickness for the opticaldiffusion coating mainly having the aluminum oxide may be about 10 toabout 15 μm. However, in embodiments when the desired lighttransmittance is 92% and even higher, the optical diffusion coatingmainly having the calcium carbonate, the halogen calcium phosphate, orthe aluminum oxide may be thinner than the minimum range valuesdescribed above.

The main material and the corresponding thickness of the opticaldiffusion coating can be decided according to the place for which theglass tube 1 is used and the light transmittance desired or required.Generally, the higher the light transmittance of the diffusion film, themore grainy the appearance of the light sources will be.

Referring to FIG. 4, the inner circumferential surface of the glass tube1 may also be provided or bonded with a reflective film 12. Thereflective film 12 is provided around the LED light sources 202, andoccupies a portion of an area of the inner circumferential surface ofthe glass tube 1 arranged along the circumferential direction thereof.As shown in FIG. 4, the reflective film 12 is disposed at two sides ofthe LED light strip 2 extending along a circumferential direction of theglass tube 1. The LED light strip 2 is basically in a middle position ofthe glass tube 1 and between the two reflective films 12. The reflectivefilm 12, when viewed by a person looking at the glass tube from the side(in the X-direction shown in FIG. 4), serves to block the LED lightsources 202, so that the person does not directly see the LED lightsources 202, thereby reducing the visual graininess effect. On the otherhand, reflection of the lights emitted from the LED light sources 202 bythe reflective film 12 facilitates the divergence angle control of theLED tube lamp, so that more light illuminates toward directions withoutthe reflective film 12, such that the LED tube lamp has higher energyefficiency when providing the same level of illumination performance.

Specifically, the reflection film 12 is provided on the inner peripheralsurface of the glass tube 1, and has an opening 12 a configured toaccommodate the LED light strip 2. The size of the opening 12 a is thesame or slightly larger than the size of the LED light strip 2. Duringassembly, the LED light sources 202 are mounted on the LED light strip 2(a bendable circuit sheet) provided on the inner surface of the glasstube 1, and then the reflective film 12 is adhered to the inner surfaceof the glass tube 1, so that the opening 12 a of the reflective film 12correspondingly matches the LED light strip 2 in a one-to-onerelationship, and the LED light strip 2 is exposed to the outside of thereflective film 12.

In one embodiment, the reflectance of the reflective film 12 isgenerally at least greater than 85%, in some embodiments greater than90%, and in some embodiments greater than 95%, to be most effective. Inone embodiment, the reflective film 12 extends circumferentially alongthe length of the glass tube 1 occupying about 30% to 50% of the innersurface area of the glass tube 1. For example, a ratio of acircumferential length of the reflective film 12 along the innercircumferential surface of the glass tube 1 to a circumferential lengthof the glass tube 1 may be about 0.3 to 0.5. In the illustratedembodiment of FIG. 4, the reflective film 12 is disposed substantiallyin the middle along a circumferential direction of the glass tube 1, sothat the two distinct portions or sections of the reflective film 12disposed on the two sides of the LED light strip 2 are substantiallyequal in area. The reflective film 12 may be made of PET with somereflective materials such as strontium phosphate or barium sulfate orany combination thereof, with a thickness between about 140 μm and about350 μm or between about 150 μm and about 220 μm for a more preferredeffect in some embodiments. As shown in FIG. 5, in other embodiments,the reflective film 12 may be provided along the circumferentialdirection of the glass tube 1 on only side of the LED light strip 2occupying the same percentage of the inner surface area of the glasstube 1 (e.g., 15% to 25% for the one side). Alternatively, as shown inFIGS. 6 and 7, the reflective film 12 may be provided without anyopening, and the reflective film 12 is directly adhered or mounted tothe inner surface of the glass tube 1 and followed by mounting or fixingthe LED light strip 2 on the reflective film 12 such that the reflectivefilm 12 positioned on one side or two sides of the LED light strip 2.

In the above mentioned embodiments, various types of the reflective film12 and the diffusion film 13 can be adopted to accomplish opticaleffects including single reflection, single diffusion, and/or combinedreflection-diffusion. For example, the glass tube 1 may be provided withonly the reflective film 12, and no diffusion film 13 is disposed insidethe glass tube 1, such as shown in FIGS. 6, 7, and 8.

In other embodiments, the width of the LED light strip 2 (along thecircumferential direction of the glass tube) can be widened to occupy acircumference area of the inner circumferential surface of the glasstube 1. According to certain embodiments, since the LED light strip 2has on its surface a circuit protective layer made of an ink which canreflect lights, the widened part of the LED light strip 2 functions likethe reflective film 12 as mentioned above. In some embodiments, a ratioof the length of the LED light strip 2 along the circumferentialdirection to the circumferential length of the glass tube 1 is about 0.2to 0.5. The light emitted from the light sources could be concentratedby the reflection of the widened part of the LED light strip 2.

In other embodiments, the inner surface of the glass made glass tube maybe coated totally with the optical diffusion coating, or partially withthe optical diffusion coating (where the reflective film 12 is coatedhave no optical diffusion coating). According to certain embodiments, nomatter in what coating manner, it is better that the optical diffusioncoating be coated on the outer surface of the rear end region of theglass tube 1 so as to firmly secure the end cap 3 with the glass tube 1.

In the present embodiments, the light emitted from the light sources maybe processed with the abovementioned diffusion film, reflective film,other kind of diffusion layer sheet, adhesive film, or any combinationthereof.

Referring again to FIG. 2, the LED tube lamp according to someembodiments also includes an adhesive sheet 4, an insulation adhesivesheet 7, and an optical adhesive sheet 8. The LED light strip 2 is fixedby the adhesive sheet 4 to an inner circumferential surface of the glasstube 1. The adhesive sheet 4 may be but is not limited to a siliconeadhesive. The adhesive sheet 4 may be in form of several short pieces ora long piece. Various kinds of the adhesive sheet 4, the insulationadhesive sheet 7, and the optical adhesive sheet 8 can be combined toconstitute various embodiments.

In one embodiment, the insulation adhesive sheet 7 is coated on thesurface of the LED light strip 2 that faces the LED light sources 202 sothat the LED light strip 2 is not exposed and thus is electricallyinsulated from the outside environment. In application of the insulationadhesive sheet 7, a plurality of through holes 71 on the insulationadhesive sheet 7 are reserved to correspondingly accommodate the LEDlight sources 202 such that the LED light sources 202 are mounted in thethrough holes 101. The material composition of the insulation adhesivesheet 7 may include, for example, vinyl silicone, hydrogen polysiloxaneand aluminum oxide. In certain embodiments, the insulation adhesivesheet 7 has a thickness ranging from about 100 μm to about 140 μm(micrometers). The insulation adhesive sheet 7 having a thickness lessthan 100 μm typically does not produce sufficient insulating effect,while the insulation adhesive sheet 7 having a thickness more than 140μm may result in material waste.

The optical adhesive sheet 8, which in some embodiments is a clear ortransparent material, is applied or coated on the surface of the LEDlight source 202 in order to facilitate optimal light transmittance.After being applied to the LED light sources 202, the optical adhesivesheet 8 may have a granular, strip-like or sheet-like shape. Theperformance of the optical adhesive sheet 8 depends on its refractiveindex and thickness. The refractive index of the optical adhesive sheet8 is in some embodiments between 1.22 and 1.6. In some embodiments, itis better for the optical adhesive sheet 8 to have a refractive indexbeing a square root of the refractive index of the housing or casing ofthe LED light source 202, or the square root of the refractive index ofthe housing or casing of the LED light source 202 plus or minus 15%, tocontribute better light transmittance. The housing/casing of the LEDlight sources 202 is a structure to accommodate and carry the LED dies(or chips) such as a LED lead frame 202 b as shown in FIG. 24. Therefractive index of the optical adhesive sheet 8 may range from 1.225 to1.253. In some embodiments, the thickness of the optical adhesive sheet8 may range from 1.1 mm to 1.3 mm. The optical adhesive sheet 8 having athickness less than 1.1 mm may not be able to cover the LED lightsources 202, while the optical adhesive sheet 8 having a thickness morethan 1.3 mm may reduce light transmittance and increases material cost.

In an exemplary process of assembling the LED light sources to the LEDlight strip, the optical adhesive sheet 8 is first applied on the LEDlight sources 202; then the insulation adhesive sheet 7 is coated on oneside of the LED light strip 2; then the LED light sources 202 are fixedor mounted on the LED light strip 2; the other side of the LED lightstrip 2 being opposite to the side of mounting the LED light sources 202is bonded and affixed to the inner surface of the glass tube 1 by theadhesive sheet 4; finally, the end cap 3 is fixed to the end portion ofthe glass tube 1, and the LED light sources 202 and the power supply 5are electrically connected by the LED light strip 2. As shown in FIG. 9,the bendable circuit sheet 2 has a freely extending portion 21 thatbends away from the glass tube 1 to be soldered or traditionallywire-bonded with the power supply 5 to form a complete LED tube lamp.

In this embodiment, the LED light strip 2 is fixed by the adhesive sheet4 to an inner circumferential surface of the glass tube 1, so as toincrease the light illumination angle of the LED tube lamp and broadenthe viewing angle to be greater than 330 degrees. By means of applyingthe insulation adhesive sheet 7 and the optical adhesive sheet 8,electrical insulation of the entire light strip 2 is accomplished suchthat electrical shock would not occur even when the glass tube 1 isbroken and therefore safety could be improved.

Furthermore, the inner peripheral surface or the outer circumferentialsurface of the glass made glass tube 1 may be covered or coated with anadhesive film (not shown) to isolate the inside from the outside of theglass made glass tube 1 when the glass made glass tube 1 is broken. Inthis embodiment, the adhesive film is coated on the inner peripheralsurface of the glass tube 1. The material for the coated adhesive filmincludes, for example, methyl vinyl silicone oil, hydro silicone oil,xylene, and calcium carbonate, wherein xylene is used as an auxiliarymaterial. The xylene will be volatilized and removed when the coatedadhesive film on the inner surface of the glass tube 1 solidifies orhardens. The xylene is mainly used to adjust the capability of adhesionand therefore to control the thickness of the coated adhesive film.

In one embodiment, the thickness of the coated adhesive film is in someexamples between about 100 and about 140 micrometers (μm). The adhesivefilm having a thickness being less than 100 micrometers may not havesufficient shatterproof capability for the glass tube, and the glasstube is thus prone to crack or shatter. The adhesive film having athickness being larger than 140 micrometers may reduce the lighttransmittance and also increases material cost. The thickness of thecoated adhesive film may be between about 10 and about 800 micrometers(μm) when the shatterproof capability and the light transmittance arenot strictly demanded.

In certain embodiments, the inner peripheral surface or the outercircumferential surface of the glass made glass tube 1 is coated with anadhesive film such that the broken pieces are adhered to the adhesivefilm when the glass made glass tube is broken. Therefore, the glass tube1 would not be penetrated to form a through hole connecting the insideand outside of the glass tube 1 and thus prevents a user from touchingany charged object inside the glass tube 1 to avoid electrical shock. Inaddition, the adhesive film is able to diffuse light and allows thelight to transmit such that the light uniformity and the lighttransmittance of the entire LED tube lamp increases. The adhesive filmcan be used in combination with the adhesive sheet 4, the insulationadhesive sheet 7 and the optical adhesive sheet 8 to constitute variousembodiments of the present disclosure. In some embodiments, when the LEDlight strip 2 is configured to be a bendable circuit sheet, no coatedadhesive film is thereby used.

In certain embodiments, a bendable circuit sheet is adopted as the LEDlight strip 2 so that such an LED light strip 2 would not allow aruptured or broken glass tube to maintain a straight shape, andtherefore would instantly inform the user of the disability of the LEDtube lamp and avoid possibly incurred electrical shock.

Referring to FIG. 10, in one embodiment, the LED light strip 2 includesa bendable circuit sheet having a metal layer 2 a and a dielectric layer2 b that are arranged in a stacked manner, wherein the metal layer 2 ais electrically conductive and may be a patterned wiring layer. Themetal layer 2 a and the dielectric layer 2 b may have same areas. TheLED light source 202 is disposed on one surface of the metal layer 2 a,the dielectric layer 2 b is disposed on the other surface of the metallayer 2 a that is away from the LED light sources 202. The metal layer 2a is electrically connected to the power supply 5 to carry directcurrent (DC) signals. Meanwhile, the surface of the dielectric layer 2 baway from the metal layer 2 a is fixed to the inner circumferentialsurface of the glass tube 1 by means of the adhesive sheet 4. Forexample, the LED light strip 2 may have a bendable circuit sheet beingmade of only the single metal layer 2 a or a two-layered structurehaving the metal layer 2 a and the dielectric layer 2 b. In this case,the structure of the bendable circuit sheet can be thinned and the metallayer originally attached to the tube wall of the glass tube can beremoved. Even more, only the single metal layer 2 a for power wiring iskept. Therefore, the LED light source utilization efficiency isimproved. This is quite different from the typical flexible circuitboard having a three-layered structure (one dielectric layer sandwichedwith two metal layers). The bendable circuit sheet is accordingly morebendable or flexible to curl when compared with the conventionalthree-layered flexible substrate. As a result, the bendable circuitsheet of the LED light strip 2 can be installed in a glass tube with acustomized shape or non-tubular shape, and fitly mounted to the innersurface of the glass tube.

In another embodiment, the outer surface of the metal layer 2 a or thedielectric layer 2 b may be covered with a circuit protective layer madeof an ink with a function of resisting soldering and increasingreflectivity. Alternatively, the dielectric layer can be omitted and themetal layer can be directly bonded to the inner circumferential surfaceof the glass tube, and the outer surface of the metal layer 2 a iscoated with the circuit protective layer. No matter whether the bendablecircuit sheet is one-layered structure made of just single metal layer 2a, or a two-layered structure made of one single metal layer 2 a and onedielectric layer 2 b, the circuit protective layer can be adopted. Thecircuit protective layer can be disposed only on one side/surface of theLED light strip 2, such as the surface having the LED light source 202.The bendable circuit sheet closely mounted to the inner surface of theglass tube is preferable in some cases. In addition, using fewer layersof the bendable circuit sheet improves the heat dissipation and lowersthe material cost.

Moreover, the length of the bendable circuit sheet could be greater thanthe length of the glass tube.

In other embodiments, the LED light strip may be replaced by a hardsubstrate such as an aluminum substrate, a ceramic substrate or afiberglass substrate having two-layered structure.

Referring to FIG. 2, in one embodiment, the LED light strip 2 has aplurality of LED light sources 202 mounted thereon, and the end cap 3has a power supply 5 installed therein. The LED light sources 202 andthe power supply 5 are electrically connected by the LED light strip 2.The power supply 5 may be a single integrated unit (i.e., all of thepower supply components are integrated into one module unit) installedin one end cap 3. Alternatively, the power supply 5 may be divided intotwo separate units (i.e. all of the power supply components are dividedinto two parts) installed in two end caps 3, respectively.

The power supply 5 can be fabricated by various ways. For example, thepower supply 5 may be an encapsulation body formed by injection moldinga silicone gel with high thermal conductivity such as being greater than0.7 w/m·k. This kind of power supply has advantages of high electricalinsulation, high heat dissipation, and regular shape to match othercomponents in an assembly. Alternatively, the power supply 5 in the endcaps may be a printed circuit board having components that are directlyexposed or packaged by a conventional heat shrink sleeve. The powersupply 5 according to some embodiments of the present disclosure can bea single printed circuit board provided with a power supply module asshown in FIG. 9 or a single integrated unit as shown in FIG. 25.

Referring to FIGS. 2 and 25, in one embodiment, the power supply 5 isprovided with a male plug 51 at one end and a metal pin 52 at the otherend, one end of the LED light strip 2 is correspondingly provided with afemale plug 201, and the end cap 3 is provided with a hollow conductivepin 301 to be connected with an outer electrical power source.Specifically, the male plug 51 is fittingly inserted into the femaleplug 201 of the LED light strip 2, while the metal pins 52 are fittinglyinserted into the hollow conductive pins 301 of the end cap 3. The maleplug 51 and the female plug 201 function as a connector between thepower supply 5 and the LED light strip 2. Upon insertion of the metalpin 502, the hollow conductive pin 301 is punched with an externalpunching tool to slightly deform such that the metal pin 502 of thepower supply 5 is secured and electrically connected to the hollowconductive pin 301. Upon turning on the electrical power, the electricalcurrent passes in sequence through the hollow conductive pin 301, themetal pin 52, the male plug 51, and the female plug 201 to reach the LEDlight strip 2 and go to the LED light sources 202. However, the powersupply 5 of the present invention is not limited to the modular type asshown in FIG. 25. The power supply 5 may be a printed circuit boardprovided with a power supply module and electrically connected to theLED light strip 2 via the abovementioned the male plug 51 and femaleplug 52 combination. In another embodiment, the power supply and the LEDlight strip may connect to each other by providing at the end of thepower supply with a female plug and at the end of the LED light stripwith a male plug. The hollow conductive pin 301 may be one or two innumber.

In another embodiment, a traditional wire bonding technique can be usedinstead of the male plug 51 and the female plug 52 for connecting anykind of the power supply 5 and the light strip 2. Furthermore, the wiresmay be wrapped with an electrically insulating tube to protect a userfrom being electrically shocked. However, the bonded wires tend to beeasily broken during transportation and can therefore cause qualityissues.

In still another embodiment, the connection between the power supply 5and the LED light strip 2 may be accomplished via tin soldering, rivetbonding, or welding. One way to secure the LED light strip 2 is toprovide the adhesive sheet 4 at one side thereof and adhere the LEDlight strip 2 to the inner surface of the glass tube 1 via the adhesivesheet 4. Two ends of the LED light strip 2 can be either fixed to ordetached from the inner surface of the glass tube 1.

In case that two ends of the LED light strip 2 are fixed to the innersurface of the glass tube 1, it may be preferable that the bendablecircuit sheet of the LED light strip 2 is provided with the female plug201 and the power supply is provided with the male plug 51 to accomplishthe connection between the LED light strip 2 and the power supply 5. Inthis case, the male plug 51 of the power supply 5 is inserted into thefemale plug 201 to establish electrically conductive.

In case that two ends of the LED light strip 2 are detached from theinner surface of the glass tube and that the LED light strip 2 isconnected to the power supply 5 via wire-bonding, any movement insubsequent transportation is likely to cause the bonded wires to break.Therefore, a desirable option for the connection between the light strip2 and the power supply 5 could be soldering. Specifically, referring toFIG. 9, the ends of the LED light strip 2 including the bendable circuitsheet are arranged to pass over and directly soldering bonded to anoutput terminal of the power supply 5 such that the product quality isimproved without using wires. In this way, the female plug 201 and themale plug 51 respectively provided for the LED light strip 2 and thepower supply 5 are no longer needed.

Referring to FIG. 11, an output terminal of the printed circuit board ofthe power supply 5 may have soldering pads “a” provided with an amountof tin solder with a thickness sufficient to later form a solder joint.Correspondingly, the ends of the LED light strip 2 may have solderingpads “b”. The soldering pads “a” on the output terminal of the printedcircuit board of the power supply 5 are soldered to the soldering pads“b” on the LED light strip 2 via the tin solder on the soldering pads“a”. The soldering pads “a” and the soldering pads “b” may be face toface during soldering such that the connection between the LED lightstrip 2 and the printed circuit board of the power supply 5 is the mostfirm. However, this kind of soldering may be implemented with athermo-compression head pressing on the rear surface of the LED lightstrip 2 and heating the tin solder, i.e. the LED light strip 2intervenes between the thermo-compression head and the tin solder, andtherefor may easily cause reliability issues. Referring to FIG. 17, athrough hole may be formed in each of the soldering pads “b” on the LEDlight strip 2 to allow the soldering pads “b” to overlay the solderingpads “b” without being face-to-face, and the thermo-compression headdirectly presses tin solders on the soldering pads “a” on surface of theprinted circuit board of the power supply 5 when the soldering pads “a”and the soldering pads “b” are vertically aligned.

Referring again to FIG. 11, two ends of the LED light strip 2 detachedfrom the inner surface of the glass tube 1 are formed as freelyextending portions 21, while most of the LED light strip 2 is attachedand secured to the inner surface of the glass tube 1. One of the freelyextending portions 21 has the soldering pads “b” as mentioned above.Upon assembling of the LED tube lamp, the freely extending end portions21 along with the soldered connection of the printed circuit board ofthe power supply 5 and the LED light strip 2 would be coiled, curled upor deformed to be fittingly accommodated inside the glass tube 1. Inthis manner, the freely extending end portions 21 may be bent away fromthe glass tube 1. In this embodiment, during the connection of the LEDlight strip 2 and the power supply 5, the soldering pads “b” and thesoldering pads “a” and the LED light sources 202 are on surfaces facingtoward the same direction and the soldering pads “b” on the LED lightstrip 2 are each formed with a through hole “e” as shown in FIG. 17 suchthat the soldering pads “b” and the soldering pads “a” communicate witheach other via the through holes “e”. When the freely extending endportions 21 are deformed due to contraction or curling up, the solderedconnection of the printed circuit board of the power supply 5 and theLED light strip 2 exerts a lateral tension on the power supply 5.Furthermore, the soldered connection of the printed circuit board of thepower supply 5 and the LED light strip 2 also exerts a downward tensionon the power supply 5 when compared with the situation where thesoldering pads “a” of the power supply 5 and the soldering pads “b” ofthe LED light strip 2 are face to face. This downward tension on thepower supply 5 comes from the tin solders inside the through holes “e”and forms a stronger and more secure electrically conductive between theLED light strip 2 and the power supply 5.

Referring to FIG. 12, in one embodiment, the soldering pads “b” of theLED light strip 2 are two separate pads to electrically connect thepositive and negative electrodes of the bendable circuit sheet of theLED light strip 2, respectively. The size of the soldering pads “b” maybe, for example, about 3.5×2 mm². The printed circuit board of the powersupply 5 is correspondingly provided with soldering pads “a” havingreserved tin solders and the height of the tin solders suitable forsubsequent automatic soldering bonding process is generally, forexample, about 0.1 to 0.7 mm, in some embodiments 0.3 to 0.5 mm, and insome even more preferable embodiments about 0.4 mm. An electricallyinsulating through hole “c” may be formed between the two soldering pads“b” to isolate and prevent the two soldering pads from electricallyshort during soldering. Furthermore, an extra positioning opening “d”may also be provided behind the electrically insulating through hole “c”to allow an automatic soldering machine to quickly recognize theposition of the soldering pads “b”.

For the sake of achieving scalability and compatibility, the amount ofthe soldering pads “b” on each end of the LED light strip 2 may be morethan one such as two, three, four, or more than four. When there is onlyone soldering pad “b” provided at each end of the LED light strip 2, thetwo ends of the LED light strip 2 are electrically connected to thepower supply 5 to form a loop, and various electrical components can beused. For example, a capacitance may be replaced by an inductance toperform current regulation. Referring to FIGS. 13 to 16, when each endof the LED light strip 2 has three soldering pads, the third solderingpad can be grounded; when each end of the LED light strip 2 has foursoldering pads, the fourth soldering pad can be used as a signal inputterminal. Correspondingly, the power supply 5 can have the same amountof soldering pads “a” as that of the soldering pads “b” on the LED lightstrip 2. According to certain embodiments, as long as electrical shortbetween the soldering pads “b” can be prevented, the soldering pads “b”can be arranged according to the dimension of the actual area fordisposition, for example, three soldering pads can be arranged in a rowor two rows. In other embodiments, the amount of the soldering pads “b”on the bendable circuit sheet of the LED light strip 2 may be reduced byrearranging the circuits on the bendable circuit sheet of the LED lightstrip 2. The lesser the amount of the soldering pads, the easier thefabrication process becomes. On the other hand, a greater number ofsoldering pads may improve and secure the electrically conductivebetween the LED light strip 2 and the output terminal of the powersupply 5.

Referring to FIG. 17, in another embodiment, each soldering pad “b” isformed with a through hole “e” having a diameter generally of about 1 to2 mm, in some embodiments of about 1.2 to 1.8 mm, and in yet someembodiments of about 1.5 mm. The through hole “e” communicates thesoldering pad “a” with the soldering pad “b” so that the tin solder onthe soldering pads “a” passes through the through holes “e” and finallyreaches the soldering pads “b”. Smaller through holes “e” would make itdifficult for the tin solder to pass. The tin solder accumulates aroundthe through holes “e” upon exiting the through holes “e” and condense toform a solder ball “g” with a larger diameter than that of the throughholes “e” upon condensing. Such a solder ball “g” functions as a rivetto further increase the stability of the electrically conductive betweenthe soldering pads “a” on the power supply 5 and the soldering pads “b”on the LED light strip 2.

Referring to FIGS. 18 to 19, in other embodiments, when a distance fromthe through hole “e” to the side edge of the LED light strip 2 is lessthan 1 mm, the tin solder may pass through the through hole “e” toaccumulate on the periphery of the through hole “e”, and extra tinsolder may spill over the soldering pads “b” to reflow along the sideedge of the LED light strip 2 and join the tin solder on the solderingpads “a” of the power supply 5. The tin solder then condenses to form astructure like a rivet to firmly secure the LED light strip 2 onto theprinted circuit board of the power supply 5 such that reliable electricconnection is achieved. Referring to FIGS. 20 and 21, in anotherembodiment, the through hole “e” can be replaced by a notch “f” formedat the side edge of the soldering pads “b” for the tin solder to easilypass through the notch “f” and accumulate on the periphery of the notch“f” and to form a solder ball with a larger diameter than that of thenotch “e” upon condensing. Such a solder ball may be formed like aC-shape rivet to enhance the secure capability of the electricallyconnecting structure.

Referring to FIGS. 22 and 23, in another embodiment, the LED light strip2 and the power supply 5 may be connected by utilizing a circuit boardassembly 25 instead of soldering bonding. The circuit board assembly 25has a long circuit sheet 251 and a short circuit board 253 that areadhered to each other with the short circuit board 253 being adjacent tothe side edge of the long circuit sheet 251. The short circuit board 253may be provided with power supply module 250 to form the power supply 5.The short circuit board 253 is stiffer or more rigid than the longcircuit sheet 251 to be able to support the power supply module 250.

The long circuit sheet 251 may be the bendable circuit sheet of the LEDlight strip including a metal layer 2 a as shown in FIG. 10. The metallayer 2 a of the long circuit sheet 251 and the power supply module 250may be electrically connected in various manners depending on the demandin practice. As shown in FIG. 22, the power supply module 250 and thelong circuit sheet 251 having the metal layer 2 a on surface are on thesame side of the short circuit board 253 such that the power supplymodule 250 is directly connected to the long circuit sheet 251. As shownin FIG. 23, alternatively, the power supply module 250 and the longcircuit sheet 251 including the metal layer 2 a on surface are onopposite sides of the short circuit board 253 such that the power supplymodule 250 is directly connected to the short circuit board 253 andindirectly connected to the a metal layer 2 a of the LED light strip 2by way of the short circuit board 253.

As shown in FIG. 22, in one embodiment, the long circuit sheet 251 andthe short circuit board 253 are adhered together first, and the powersupply module 250 is subsequently mounted on the metal layer 2 a of thelong circuit sheet 251 serving as the LED light strip 2. The longcircuit sheet 251 of the LED light strip 2 herein is not limited toinclude only one metal layer 2 a and may further include another metallayer such as the metal layer 2 c shown in FIG. 48. The light sources202 are disposed on the metal layer 2 a of the LED light strip 2 andelectrically connected to the power supply 5 by way of the metal layer 2a. As shown in FIG. 23, in another embodiment, the long circuit sheet251 of the LED light strip 2 may include a metal layer 2 a and adielectric layer 2 b. In one embodiment, the dielectric layer 2 b may beadhered to the short circuit board 253 first and the metal layer 2 a issubsequently adhered to the dielectric layer 2 b and extends to theshort circuit board 253. All these embodiments are within the scope ofapplying the circuit board assembly concept of the present disclosure.

In the above-mentioned embodiments, the short circuit board 253 may havea length generally of about 15 mm to about 40 mm and in some embodimentsabout 19 mm to about 36 mm, while the long circuit sheet 251 may have alength generally of about 800 mm to about 2800 mm and in someembodiments of about 1200 mm to about 2400 mm. A ratio of the length ofthe short circuit board 253 to the length of the long circuit sheet 251ranges from, for example, about 1:20 to about 1:200.

When the ends of the LED light strip 2 are not fixed on the innersurface of the glass tube 1, the connection between the LED light strip2 and the power supply 5 via soldering bonding could not firmly supportthe power supply 5, and it may be necessary to dispose the power supply5 inside the end cap 3. For example, a longer end cap to have enoughspace for receiving the power supply 5 would be needed. However, thiswill reduce the length of the glass tube under the prerequisite that thetotal length of the LED tube lamp is fixed according to the productstandard, and may therefore decrease the effective illuminating areas.

Next, examples of the circuit design and using of the power supplymodule 250 are described as follows.

FIG. 28A is a block diagram of a power supply system for an LED tubelamp according to an embodiment of the present invention. Referring toFIG. 28A, an AC power supply 508 is used to supply an AC supply signal,and may be an AC powerline with a voltage rating, for example, in100-277 volts and a frequency rating, for example, of 50 or 60 Hz. Alamp driving circuit 505 receives and then converts the AC supply signalinto an AC driving signal as an external driving signal. Lamp drivingcircuit 505 may be for example an electronic ballast used to convert theAC powerline into a high-frequency high-voltage AC driving signal.Common types of electronic ballast include instant-start ballast,program-start or rapid-start ballast, etc., which may all be applicableto the LED tube lamp of the present invention. The voltage of the ACdriving signal is likely higher than 300 volts, and is in someembodiments in the range of about 400-700 volts. The frequency of the ACdriving signal is likely higher than 10 k Hz, and is in some embodimentsin the range of about 20 k-50 k Hz. The LED tube lamp 500 receives anexternal driving signal and is thus driven to emit light. In oneembodiment, the external driving signal comprises the AC driving signalfrom lamp driving circuit 505. In one embodiment, LED tube lamp 500 isin a driving environment in which it is power-supplied at its one endcap having two conductive pins 501 and 502, which are coupled to lampdriving circuit 505 to receive the AC driving signal. The two conductivepins 501 and 502 may be electrically connected to, either directly orindirectly, the lamp driving circuit 505.

It is worth noting that lamp driving circuit 505 may be omitted and istherefore depicted by a dotted line. In one embodiment, if lamp drivingcircuit 505 is omitted, AC power supply 508 is directly connected topins 501 and 502, which then receive the AC supply signal as an externaldriving signal.

In addition to the above use with a single-end power supply, LED tubelamp 500 may instead be used with a dual-end power supply to one pin ateach of the two ends of an LED lamp tube. FIG. 28B is a block diagram ofa power supply system for an LED tube lamp according to one embodimentof the present invention. Referring to FIG. 28B, compared to that shownin FIG. 28A, pins 501 and 502 are respectively disposed at the twoopposite end caps of LED tube lamp 500, forming a single pin at each endof LED tube lamp 500, with other components and their functions beingthe same as those in FIG. 28A.

FIG. 28C is a block diagram of an LED lamp according to one embodimentof the present invention. Referring to FIG. 28C, the power supply moduleof the LED lamp summarily includes a rectifying circuit 510, and afiltering circuit 520. Rectifying circuit 510 is coupled to pins 501 and502 to receive and then rectify an external driving signal, so as tooutput a rectified signal at output terminals 511 and 512. The externaldriving signal may be the AC driving signal or the AC supply signaldescribed with reference to FIGS. 28A and 28B, or may even be a DCsignal, which embodiments do not alter the LED lamp of the presentinvention. Filtering circuit 520 is coupled to the first rectifyingcircuit for filtering the rectified signal to produce a filtered signal,as recited in the claims. For instance, filtering circuit 520 is coupledto terminals 511 and 512 to receive and then filter the rectifiedsignal, so as to output a filtered signal at output terminals 521 and522. An LED lighting module 530 is coupled to filtering circuit 520, toreceive the filtered signal for emitting light. For instance, LEDlighting module 530 may be a circuit coupled to terminals 521 and 522 toreceive the filtered signal and thereby to drive an LED unit (not shown)in LED lighting module 530 to emit light. Details of these operationsare described in below descriptions of certain embodiments.

It is worth noting that although there are two output terminals 511 and512 and two output terminals 521 and 522 in embodiments of these Figs.,in practice the number of ports or terminals for coupling betweenrectifying circuit 510, filtering circuit 520, and LED lighting module530 may be one or more depending on the needs of signal transmissionbetween the circuits or devices.

In addition, the power supply module of the LED lamp described in FIG.28C, and embodiments of the power supply module of an LED lamp describedbelow, may each be used in the LED tube lamp 500 in FIGS. 28A and 28B,and may instead be used in any other type of LED lighting structurehaving two conductive pins used to conduct power, such as LED lightbulbs, personal area lights (PAL), plug-in LED lamps with differenttypes of bases (such as types of PL-S, PL-D, PL-T, PL-L, etc.), etc.

FIG. 28D is a block diagram of a power supply system for an LED tubelamp according to an embodiment of the present invention. Referring toFIG. 28D, an AC power supply 508 is used to supply an AC supply signal.A lamp driving circuit 505 receives and then converts the AC supplysignal into an AC driving signal. An LED tube lamp 500 receives an ACdriving signal from lamp driving circuit 505 and is thus driven to emitlight. In this embodiment, LED tube lamp 500 is power-supplied at itsboth end caps respectively having two pins 501 and 502 and two pins 503and 504, which are coupled to lamp driving circuit 505 to concurrentlyreceive the AC driving signal to drive an LED unit (not shown) in LEDtube lamp 500 to emit light. AC power supply 508 may be e.g. the ACpowerline, and lamp driving circuit 505 may be a stabilizer or anelectronic ballast.

FIG. 28E is a block diagram of an LED lamp according to an embodiment ofthe present invention. Referring to FIG. 28E, the power supply module ofthe LED lamp, which as described above may be included in an end cap ofthe LED tube lamp, summarily includes a rectifying circuit 510, afiltering circuit 520, and a filtering circuit 540. Rectifying circuit510 is coupled to pins 501 and 502 to receive and then rectify anexternal driving signal conducted by pins 501 and 502. Rectifyingcircuit 540 is coupled to pins 503 and 504 to receive and then rectifyan external driving signal conducted by pins 503 and 504. Therefore, thepower supply module of the LED lamp may include two rectifying circuits510 and 540 configured to output a rectified signal at output terminals511 and 512. Filtering circuit 520 is coupled to terminals 511 and 512to receive and then filter the rectified signal, so as to output afiltered signal at output terminals 521 and 522. An LED lighting module530 is coupled to terminals 521 and 522 to receive the filtered signaland thereby to drive an LED unit (not shown) in LED lighting module 530to emit light.

The power supply module of the LED lamp in this embodiment of FIG. 28Emay be used in LED tube lamp 500 with a dual-end power supply in FIG.28D. Since the power supply module of the LED lamp comprises rectifyingcircuits 510 and 540, the power supply module of the LED lamp may beused in LED tube lamp 500 with a single-end power supply in FIGS. 28Aand 28B, to receive an external driving signal (such as the AC supplysignal or the AC driving signal described above). The power supplymodule of an LED lamp in this embodiment and other embodiments hereinmay also be used with a DC driving signal.

FIG. 29A is a schematic diagram of a rectifying circuit according to anembodiment of the present invention. Referring to FIG. 29A, rectifyingcircuit 610 includes rectifying diodes 611, 612, 613, and 614,configured to full-wave rectify a received signal. Diode 611 has ananode connected to output terminal 512, and a cathode connected to pin502. Diode 612 has an anode connected to output terminal 512, and acathode connected to pin 501. Diode 613 has an anode connected to pin502, and a cathode connected to output terminal 511. Diode 614 has ananode connected to pin 501, and a cathode connected to output terminal511.

When pins 501 and 502 receive an AC signal, rectifying circuit 610operates as follows. During the connected AC signal's positive halfcycle, the AC signal is input through pin 501, diode 614, and outputterminal 511 in sequence, and later output through output terminal 512,diode 611, and pin 502 in sequence. During the connected AC signal'snegative half cycle, the AC signal is input through pin 502, diode 613,and output terminal 511 in sequence, and later output through outputterminal 512, diode 612, and pin 501 in sequence. Therefore, during theconnected AC signal's full cycle, the positive pole of the rectifiedsignal produced by rectifying circuit 610 remains at output terminal511, and the negative pole of the rectified signal remains at outputterminal 512. Accordingly, the rectified signal produced or output byrectifying circuit 610 is a full-wave rectified signal.

When pins 501 and 502 are coupled to a DC power supply to receive a DCsignal, rectifying circuit 610 operates as follows. When pin 501 iscoupled to the anode of the DC supply and pin 502 to the cathode of theDC supply, the DC signal is input through pin 501, diode 614, and outputterminal 511 in sequence, and later output through output terminal 512,diode 611, and pin 502 in sequence. When pin 501 is coupled to thecathode of the DC supply and pin 502 to the anode of the DC supply, theDC signal is input through pin 502, diode 613, and output terminal 511in sequence, and later output through output terminal 512, diode 612,and pin 501 in sequence. Therefore, no matter what the electricalpolarity of the DC signal is between pins 501 and 502, the positive poleof the rectified signal produced by rectifying circuit 610 remains atoutput terminal 511, and the negative pole of the rectified signalremains at output terminal 512.

Therefore, rectifying circuit 610 in this embodiment can output orproduce a proper rectified signal regardless of whether the receivedinput signal is an AC or DC signal.

FIG. 29B is a schematic diagram of a rectifying circuit according to anembodiment of the present invention. Referring to FIG. 29B, rectifyingcircuit 710 includes rectifying diodes 711 and 712, configured tohalf-wave rectify a received signal. Diode 711 has an anode connected topin 502, and a cathode connected to output terminal 511. Diode 712 hasan anode connected to output terminal 511, and a cathode connected topin 501. Output terminal 512 may be omitted or grounded depending onactual applications.

Next, exemplary operation(s) of rectifying circuit 710 is described asfollows.

In one embodiment, during a received AC signal's positive half cycle,the electrical potential at pin 501 is higher than that at pin 502, sodiodes 711 and 712 are both in a cutoff state as being reverse-biased,making rectifying circuit 710 not outputting a rectified signal. Duringa received AC signal's negative half cycle, the electrical potential atpin 501 is lower than that at pin 502, so diodes 711 and 712 are both ina conducting state as being forward-biased, allowing the AC signal to beinput through diode 711 and output terminal 511, and later outputthrough output terminal 512, a ground terminal, or another end of theLED tube lamp not directly connected to rectifying circuit 710.Accordingly, the rectified signal produced or output by rectifyingcircuit 710 is a half-wave rectified signal.

FIG. 29C is a schematic diagram of a rectifying circuit according to anembodiment of the present invention. Referring to FIG. 29C, rectifyingcircuit 810 includes a rectifying unit 815 and a terminal adaptercircuit 541. In this embodiment, rectifying unit 815 comprises ahalf-wave rectifier circuit including diodes 811 and 812 and configuredto half-wave rectify. Diode 811 has an anode connected to an outputterminal 512, and a cathode connected to a half-wave node 819. Diode 812has an anode connected to half-wave node 819, and a cathode connected toan output terminal 511. Terminal adapter circuit 541 is coupled tohalf-wave node 819 and pins 501 and 502, to transmit a signal receivedat pin 501 and/or pin 502 to half-wave node 819. By means of theterminal adapting function of terminal adapter circuit 541, rectifyingcircuit 810 allows of two input terminals (connected to pins 501 and502) and two output terminals 511 and 512.

Next, in certain embodiments, rectifying circuit 810 operates asfollows.

During a received AC signal's positive half cycle, the AC signal may beinput through pin 501 or 502, terminal adapter circuit 541, half-wavenode 819, diode 812, and output terminal 511 in sequence, and lateroutput through another end or circuit of the LED tube lamp. During areceived AC signal's negative half cycle, the AC signal may be inputthrough another end or circuit of the LED tube lamp, and later outputthrough output terminal 512, diode 811, half-wave node 819, terminaladapter circuit 541, and pin 501 or 502 in sequence.

In certain embodiments, terminal adapter circuit 541 may comprise aresistor, a capacitor, an inductor, or any combination thereof, forperforming functions of voltage/current regulation or limiting, types ofprotection, current/voltage regulation, etc. Descriptions of thesefunctions are presented below.

In practice, rectifying unit 815 and terminal adapter circuit 541 may beinterchanged in position (as shown in FIG. 29D), without altering thefunction of half-wave rectification. FIG. 29D is a schematic diagram ofa rectifying circuit according to one embodiment. Referring to FIG. 29D,diode 811 has an anode connected to pin 502 and diode 812 has a cathodeconnected to pin 501. A cathode of diode 811 and an anode of diode 812are connected to half-wave node 819. Terminal adapter circuit 541 iscoupled to half-wave node 819 and output terminals 511 and 512. During areceived AC signal's positive half cycle, the AC signal may be inputthrough another end or circuit of the LED tube lamp, and later outputthrough output terminal 512 or 512, terminal adapter circuit 541,half-wave node 819, diode 812, and pin 501 in sequence. During areceived AC signal's negative half cycle, the AC signal may be inputthrough pin 502, diode 811, half-wave node 819, terminal adapter circuit541, and output node 511 or 512 in sequence, and later output throughanother end or circuit of the LED tube lamp.

Terminal adapter circuit 541 in embodiments shown in FIGS. 29C and 29Dmay be omitted and is therefore depicted by a dotted line. If terminaladapter circuit 541 of FIG. 29C is omitted, pins 501 and 502 will becoupled to half-wave node 819. If terminal adapter circuit 541 of FIG.29D is omitted, output terminals 511 and 512 will be coupled tohalf-wave node 819.

Rectifying circuit 510 as shown and explained in FIGS. 29A-D canconstitute or be the rectifying circuit 540 shown in FIG. 28E, as havingpins 503 and 504 for conducting instead of pins 501 and 502.

Next, an explanation follows as to choosing embodiments and theircombinations of rectifying circuits 510 and 540, with reference to FIGS.28C and 28E.

Rectifying circuit 510 in embodiments shown in FIG. 28C may comprise therectifying circuit 610 in FIG. 29A.

Rectifying circuits 510 and 540 in embodiments shown in FIG. 28E mayeach comprise any one of the rectifying circuits in FIGS. 29A-D, andterminal adapter circuit 541 in FIGS. 29C-D may be omitted withoutaltering the rectification function needed in an LED tube lamp. Whenrectifying circuits 510 and 540 each comprise a half-wave rectifiercircuit described in FIGS. 29B-D, during a received AC signal's positiveor negative half cycle, the AC signal may be input from one ofrectifying circuits 510 and 540, and later output from the otherrectifying circuit 510 or 540. Further, when rectifying circuits 510 and540 each comprise the rectifying circuit described in FIG. 29C or 50D,or when they comprise the rectifying circuits in FIGS. 29C and 29Drespectively, only one terminal adapter circuit 541 may be needed forfunctions of voltage/current regulation or limiting, types ofprotection, current/voltage regulation, etc. within rectifying circuits510 and 540, omitting another terminal adapter circuit 541 withinrectifying circuit 510 or 540.

FIG. 30A is a schematic diagram of the terminal adapter circuitaccording to an embodiment of the present invention. Referring to FIG.30A, terminal adapter circuit 641 comprises a capacitor 642 having anend connected to pins 501 and 502, and another end connected tohalf-wave node 819. Capacitor 642 has an equivalent impedance to an ACsignal, which impedance increases as the frequency of the AC signaldecreases, and decreases as the frequency increases. Therefore,capacitor 642 in terminal adapter circuit 641 in this embodiment worksas a high-pass filter. Further, terminal adapter circuit 641 isconnected in series to an LED unit in the LED tube lamp, producing anequivalent impedance of terminal adapter circuit 641 to perform acurrent/voltage limiting function on the LED unit, thereby preventingdamaging of the LED unit by an excessive voltage across and/or currentin the LED unit. In addition, choosing the value of capacitor 642according to the frequency of the AC signal can further enhancevoltage/current regulation.

Terminal adapter circuit 641 may further include a capacitor 645 and/orcapacitor 646. Capacitor 645 has an end connected to half-wave node 819,and another end connected to pin 503. Capacitor 646 has an end connectedto half-wave node 819, and another end connected to pin 504. Forexample, half-wave node 819 may be a common connective node betweencapacitors 645 and 646. And capacitor 642 acting as a current regulatingcapacitor is coupled to the common connective node and pins 501 and 502.In such a structure, series-connected capacitors 642 and 645 existbetween one of pins 501 and 502 and pin 503, and/or series-connectedcapacitors 642 and 646 exist between one of pins 501 and 502 and pin504. Through equivalent impedances of series-connected capacitors,voltages from the AC signal are divided. Referring to FIGS. 28E and 30A,according to ratios between equivalent impedances of theseries-connected capacitors, the voltages respectively across capacitor642 in rectifying circuit 510, filtering circuit 520, and LED lightingmodule 530 can be controlled, making the current flowing through an LEDmodule in LED lighting module 530 being limited within a current rating,and then protecting/preventing filtering circuit 520 and LED lightingmodule 530 from being damaged by excessive voltages.

FIG. 30B is a schematic diagram of the terminal adapter circuitaccording to one embodiment. Referring to FIG. 30B, terminal adaptercircuit 741 comprises capacitors 743 and 744. Capacitor 743 has an endconnected to pin 501, and another end connected to half-wave node 819.Capacitor 744 has an end connected to pin 502, and another end connectedto half-wave node 819. Compared to terminal adapter circuit 641 in FIG.30A, terminal adapter circuit 741 has capacitors 743 and 744 in place ofcapacitor 642. Capacitance values of capacitors 743 and 744 may be thesame as each other, or may differ from each other depending on themagnitudes of signals to be received at pins 501 and 502.

Similarly, terminal adapter circuit 741 may further comprise a capacitor745 and/or a capacitor 746, respectively connected to pins 503 and 504.Thus, each of pins 501 and 502 and each of pins 503 and 504 may beconnected in series to a capacitor, to achieve the functions of voltagedivision and other protections.

FIG. 30C is a schematic diagram of the terminal adapter circuitaccording to one embodiment. Referring to FIG. 30C, terminal adaptercircuit 841 comprises capacitors 842, 843, and 844. Capacitors 842 and843 are connected in series between pin 501 and half-wave node 819.Capacitors 842 and 844 are connected in series between pin 502 andhalf-wave node 819. In such a circuit structure, if any one ofcapacitors 842, 843, and 844 is shorted, there is still at least onecapacitor (of the other two capacitors) between pin 501 and half-wavenode 819 and between pin 502 and half-wave node 819, which performs acurrent-limiting function. Therefore, in the event that a useraccidentally gets an electric shock, this circuit structure will preventan excessive current flowing through and then seriously hurting the bodyof the user.

Similarly, terminal adapter circuit 841 may further comprise a capacitor845 and/or a capacitor 846, respectively connected to pins 503 and 504.Thus, each of pins 501 and 502 and each of pins 503 and 504 may beconnected in series to a capacitor, to achieve the functions of voltagedivision and other protections.

FIG. 30D is a schematic diagram of the terminal adapter circuitaccording to one embodiment. Referring to FIG. 30D, terminal adaptercircuit 941 comprises fuses 947 and 948. Fuse 947 has an end connectedto pin 501, and another end connected to half-wave node 819. Fuse 948has an end connected to pin 502, and another end connected to half-wavenode 819. With the fuses 947 and 948, when the current through each ofpins 501 and 502 exceeds a current rating of a corresponding connectedfuse 947 or 948, the corresponding fuse 947 or 948 will accordingly meltand then break the circuit to achieve overcurrent protection.

Each of the embodiments of the terminal adapter circuits as inrectifying circuits 510 and 810 coupled to pins 501 and 502 and shownand explained above can be used or included in the rectifying circuit540 shown in FIG. 28E, as when conductive pins 503 and 504 andconductive pins 501 and 502 are interchanged in position.

Capacitance values of the capacitors in the embodiments of the terminaladapter circuits shown and described above are in some embodiments inthe range, for example, of about 100 pF-100 nF. Also, a capacitor usedin embodiments may be equivalently replaced by two or more capacitorsconnected in series or parallel. For example, each of capacitors 642 and842 may be replaced by two series-connected capacitors, one having acapacitance value chosen from the range, for example of about 1.0 nF toabout 2.5 nF and which may be in some embodiments preferably 1.5 nF, andthe other having a capacitance value chosen from the range, for exampleof about 1.5 nF to about 3.0 nF, and which is in some embodiments about2.2 nF.

FIG. 31A is a schematic diagram of an LED module according to oneembodiment. Referring to FIG. 31A, LED module 630 in the LED lightingmodule has an anode connected to the filtering output terminal 521, hasa cathode connected to the filtering output terminal 522, and comprisesat least one LED unit 632. When two or more LED units are included, theyare connected in parallel. The anode of each LED unit 632 is connectedto the anode of LED module 630 and thus output terminal 521, and thecathode of each LED unit 632 is connected to the cathode of LED module630 and thus output terminal 522. Each LED unit 632 includes at leastone LED 631. When multiple LEDs 631 are included in an LED unit 632,they are connected in series, with the anode of the first LED 631connected to the anode of this LED unit 632, and the cathode of thefirst LED 631 connected to the next or second LED 631. And the anode ofthe last LED 631 in this LED unit 632 is connected to the cathode of aprevious LED 631, with the cathode of the last LED 631 connected to thecathode of this LED unit 632.

LED module 630 may produce a current detection signal S531 reflecting amagnitude of current through LED module 630 and used for controlling ordetecting on the LED module 630.

FIG. 31B is a schematic diagram of an LED module according to oneembodiment. Referring to FIG. 31B, LED module 630 has an anode connectedto the filtering output terminal 521, has a cathode connected to thefiltering output terminal 522, and comprises at least two LED units 732,with the anode of each LED unit 732 connected to the anode of LED module630, and the cathode of each LED unit 732 connected to the cathode ofLED module 630. Each LED unit 732 includes at least two LEDs 731connected in the same way as described in FIG. 31A. For example, theanode of the first LED 731 in an LED unit 732 is connected to the anodeof this LED unit 732, the cathode of the first LED 731 is connected tothe anode of the next or second LED 731, and the cathode of the last LED731 is connected to the cathode of this LED unit 732. Further, LED units732 in an LED module 630 are connected to each other in this embodiment.All of the n-th LEDs 731 respectively of the LED units 732 are connectedby every anode of every n-th LED 731 in the LED units 732, and by everycathode of every n-th LED 731, where n is a positive integer. In thisway, the LEDs in LED module 630 in this embodiment are connected in theform of a mesh.

In some examples, the LED lighting module 530 of the above embodimentsincludes LED module 630, but doesn't include a driving circuit for theLED module 630.

Similarly, LED module 630 in these examples may produce a currentdetection signal S531 reflecting a magnitude of current through LEDmodule 630 and used for controlling or detecting on the LED module 630.

The number of LEDs 731 included by an LED unit 732 is in someembodiments in the range of 15-25, and is may be in some specificembodiments in the range of 18-22.

FIG. 31C is a plan view of a circuit layout of the LED module accordingto an embodiment of the present invention. Referring to FIG. 31C, inthis embodiment LEDs 831 are connected in the same way as described inFIG. 31B, and three LED units are assumed in LED module 630 anddescribed as follows for illustration. A positive conductive line 834and a negative conductive line 835 are to receive a driving signal, forsupplying power to the LEDs 831. For example, positive conductive line834 may be coupled to the filtering output terminal 521 of the filteringcircuit 520 described above, and negative conductive line 835 coupled tothe filtering output terminal 522 of the filtering circuit 520, toreceive a filtered signal. For the convenience of illustration, allthree of the n-th LEDs 831 respectively of the three LED units aregrouped as an LED set 833 in FIG. 31C.

Positive conductive line 834 connects the three first LEDs 831respectively of the leftmost three LED units, at the anodes on the leftsides of the three first LEDs 831 as shown in the leftmost LED set 833of FIG. 31C. Negative conductive line 835 connects the three last LEDs831 respectively of the leftmost three LED units, at the cathodes on theright sides of the three last LEDs 831 as shown in the rightmost LED set833 of FIG. 31C. And of the three LED units, the cathodes of the threefirst LEDs 831, the anodes of the three last LEDs 831, and the anodesand cathodes of all the remaining LEDs 831 are connected by conductivelines or parts 839.

For example, the anodes of the three LEDs 831 in the first, leftmost LEDset 833 may be connected together by positive conductive line 834, andtheir cathodes may be connected together by a leftmost conductive part839. The anodes of the three LEDs 831 in the second, next-leftmost LEDset 833 are also connected together by the leftmost conductive part 839,whereas their cathodes are connected together by a second, next-leftmostconductive part 839. Since the cathodes of the three LEDs 831 in theleftmost LED set 833 and the anodes of the three LEDs 831 in the secondleftmost LED set 833 are connected together by the same leftmostconductive part 839, in each of the three LED units the cathode of thefirst LED 831 is connected to the anode of the next or second LED 831,with the remaining LEDs 831 also being connected in the same way.Accordingly, all the LEDs 831 of the three LED units are connected toform the mesh as shown in FIG. 31B.

In this embodiment the length 836 of a portion of each conductive part839 that immediately connects to the anode of an LED 831 is smaller thanthe length 837 of another portion of each conductive part 839 thatimmediately connects to the cathode of an LED 831, making the area ofthe latter portion immediately connecting to the cathode larger thanthat of the former portion immediately connecting to the anode. Thelength 837 may be smaller than a length 838 of a portion of eachconductive part 839 that immediately connects the cathode of an LED 831and the anode of the next LED 831, making the area of the portion ofeach conductive part 839 that immediately connects a cathode and ananode larger than the area of any other portion of each conductive part839 that immediately connects to only a cathode or an anode of an LED831. Due to the length differences and area differences, this layoutstructure improves heat dissipation of the LEDs 831.

In some embodiments, positive conductive line 834 includes a lengthwiseportion 834 a, and negative conductive line 835 includes a lengthwiseportion 835 a, which are conducive to making the LED module have apositive “+” connective portion and a negative “−” connective portion ateach of the two ends of the LED module, as shown in FIG. 31C. Such alayout structure allows for coupling any of other circuits of the powersupply module of the LED lamp, including e.g. filtering circuit 520 andrectifying circuits 510 and 540, to the LED module through the positiveconnective portion and/or the negative connective portion at each orboth ends of the LED lamp. Thus the layout structure increases theflexibility in arranging actual circuits in the LED lamp.

FIG. 31D is a plan view of a circuit layout of the LED module accordingto another embodiment. Referring to FIG. 31D, in this embodiment LEDs931 are connected in the same way as described in FIG. 31A, and threeLED units each including 7 LEDs 931 are assumed in LED module 630 anddescribed as follows for illustration. A positive conductive line 934and a negative conductive line 935 are to receive a driving signal, forsupplying power to the LEDs 931. For example, positive conductive line934 may be coupled to the filtering output terminal 521 of the filteringcircuit 520 described above, and negative conductive line 935 coupled tothe filtering output terminal 522 of the filtering circuit 520, toreceive a filtered signal. For the convenience of illustration, allseven LEDs 931 of each of the three LED units are grouped as an LED set932 in FIG. 31D. Thus there are three LED sets 932 corresponding to thethree LED units.

Positive conductive line 934 connects to the anode on the left side ofthe first or leftmost LED 931 of each of the three LED sets 932.Negative conductive line 935 connects to the cathode on the right sideof the last or rightmost LED 931 of each of the three LED sets 932. Ineach LED set 932, of two consecutive LEDs 931 the LED 931 on the lefthas a cathode connected by a conductive part 939 to an anode of the LED931 on the right. By such a layout, the LEDs 931 of each LED set 932 areconnected in series.

A conductive part 939 may be used to connect an anode and a cathoderespectively of two consecutive LEDs 931. Negative conductive line 935connects to the cathode of the last or rightmost LED 931 of each of thethree LED sets 932. And positive conductive line 934 connects to theanode of the first or leftmost LED 931 of each of the three LED sets932. Therefore, as shown in FIG. 31D, the length (and thus area) of theconductive part 939 is larger than that of the portion of negativeconductive line 935 immediately connecting to a cathode, which length(and thus area) is then larger than that of the portion of positiveconductive line 934 immediately connecting to an anode. For example, thelength 938 of the conductive part 939 may be larger than the length 937of the portion of negative conductive line 935 immediately connecting toa cathode of an LED 931, which length 937 is then larger than the length936 of the portion of positive conductive line 934 immediatelyconnecting to an anode of an LED 931. Such a layout structure improvesheat dissipation of the LEDs 931 in LED module 630.

Positive conductive line 934 may include a lengthwise portion 934 a, andnegative conductive line 935 may include a lengthwise portion 935 a,which are conducive to making the LED module have a positive “+”connective portion and a negative “−” connective portion at each of thetwo ends of the LED module, as shown in FIG. 31D. Such a layoutstructure allows for coupling any of other circuits of the power supplymodule of the LED lamp, including e.g. filtering circuit 520 andrectifying circuits 510 and 540, to the LED module through the positiveconnective portion 934 a and/or the negative connective portion 935 a ateach or both ends of the LED lamp. Thus the layout structure increasesthe flexibility in arranging actual circuits in the LED lamp.

Further, the circuit layouts as shown in FIGS. 31C and 31D may beimplemented with a bendable circuit sheet or substrate, which may bereferred to as a flexible circuit board. For example, the bendablecircuit sheet may comprise one conductive layer where positiveconductive line 834, positive lengthwise portion 834 a, negativeconductive line 835, negative lengthwise portion 835 a, and conductiveparts 839 shown in FIG. 31C, and positive conductive line 934, positivelengthwise portion 934 a, negative conductive line 935, negativelengthwise portion 935 a, and conductive parts 939 shown in FIG. 31D areformed by the method of etching.

FIG. 31E is a plan view of a circuit layout of the LED module accordingto another embodiment. The layout structures of the LED module in FIGS.31E and 31C each correspond to the same way of connecting LEDs 831 asthat shown in FIG. 31B, but the layout structure in FIG. 31E comprisestwo conductive layers, instead of only one conductive layer for formingthe circuit layout as shown in FIG. 31C. Referring to FIG. 31E, the maindifference from the layout in FIG. 31C is that positive conductive line834 and negative conductive line 835 have a lengthwise portion 834 a anda lengthwise portion 835 a, respectively, that are formed in a secondconductive layer instead. The difference is elaborated as follows.

Referring to FIG. 31E, the bendable circuit sheet of the LED modulecomprises a first conductive layer 2 a and a second conductive layer 2 celectrically insulated from each other by a dielectric layer 2 b (notshown). Of the two conductive layers, positive conductive line 834,negative conductive line 835, and conductive parts 839 in FIG. 31E areformed in first conductive layer 2 a by the method of etching forelectrically connecting the plurality of LED components 831 e.g. in aform of a mesh, whereas positive lengthwise portion 834 a and negativelengthwise portion 835 a are formed in second conductive layer 2 c byetching for electrically connecting to (the filtering output terminalof) the filtering circuit. Further, positive conductive line 834 andnegative conductive line 835 in first conductive layer 2 a have viapoints 834 b and via points 835 b, respectively, for connecting tosecond conductive layer 2 c. And positive lengthwise portion 834 a andnegative lengthwise portion 835 a in second conductive layer 2 c havevia points 834 c and via points 835 c, respectively. Via points 834 bare positioned corresponding to via points 834 c, for connectingpositive conductive line 834 and positive lengthwise portion 834 a. Viapoints 835 b are positioned corresponding to via points 835 c, forconnecting negative conductive line 835 and negative lengthwise portion835 a. A useful way of connecting the two conductive layers is to form ahole connecting each via point 834 b and a corresponding via point 834c, and to form a hole connecting each via point 835 b and acorresponding via point 835 c, with the holes extending through the twoconductive layers and the dielectric layer in-between. And positiveconductive line 834 and positive lengthwise portion 834 a can beelectrically connected by welding metallic part(s) through theconnecting hole(s), and negative conductive line 835 and negativelengthwise portion 835 a can be electrically connected by weldingmetallic part(s) through the connecting hole(s).

Similarly, the layout structure of the LED module in FIG. 31D mayalternatively have positive lengthwise portion 934 a and negativelengthwise portion 935 a disposed in a second conductive layer, toconstitute a two-layer layout structure.

The thickness of the second conductive layer of a two-layer bendablecircuit sheet is in some embodiments larger than that of the firstconductive layer, in order to reduce the voltage drop or loss along eachof the positive lengthwise portion and the negative lengthwise portiondisposed in the second conductive layer. Compared to a one-layerbendable circuit sheet, since a positive lengthwise portion and anegative lengthwise portion are disposed in a second conductive layer ina two-layer bendable circuit sheet, the width (between two lengthwisesides) of the two-layer bendable circuit sheet is or can be reduced. Onthe same fixture or plate in a production process, the number ofbendable circuit sheets each with a shorter width that can be laidtogether at most is larger than the number of bendable circuit sheetseach with a longer width that can be laid together at most. Thusadopting a bendable circuit sheet with a shorter width can increase theefficiency of production of the LED module. And reliability in theproduction process, such as the accuracy of welding position whenwelding (materials on) the LED components, can also be improved, becausea two-layer bendable circuit sheet can better maintain its shape.

As a variant of the above embodiments, a type of LED tube lamp isprovided that has at least some of the electronic components of itspower supply module disposed on a light strip of the LED tube lamp. Forexample, the technique of printed electronic circuit (PEC) can be usedto print, insert, or embed at least some of the electronic componentsonto the light strip.

In one embodiment, all electronic components of the power supply moduleare disposed on the light strip. The production process may include orproceed with the following steps: preparation of the circuit substrate(e.g. preparation of a flexible printed circuit board); ink jet printingof metallic nano-ink; ink jet printing of active and passive components(as of the power supply module); drying/sintering; ink jet printing ofinterlayer bumps; spraying of insulating ink; ink jet printing ofmetallic nano-ink; ink jet printing of active and passive components (tosequentially form the included layers); spraying of surface bond pad(s);and spraying of solder resist against LED components.

In certain embodiments, if all electronic components of the power supplymodule are disposed on the light strip, electrical connection betweenterminal pins of the LED tube lamp and the light strip may be achievedby connecting the pins to conductive lines which are welded with ends ofthe light strip. In this case, another substrate for supporting thepower supply module is not required, thereby allowing of an improveddesign or arrangement in the end cap(s) of the LED tube lamp. In someembodiments, components of the power supply module are disposed at twoends of the light strip, in order to significantly reduce the impact ofheat generated from the power supply module's operations on the LEDcomponents. Since no substrate other than the light strip is used tosupport the power supply module in this case, the total amount ofwelding or soldering can be significantly reduced, improving the generalreliability of the power supply module.

Another case is that some of all electronic components of the powersupply module, such as some resistors and/or smaller size capacitors,are printed onto the light strip, and some bigger size components, suchas some inductors and/or electrolytic capacitors, are disposed in theend cap(s). The production process of the light strip in this case maybe the same as that described above. And in this case disposing some ofall electronic components on the light strip is conducive to achieving areasonable layout of the power supply module in the LED tube lamp, whichmay allow of an improved design in the end cap(s).

As a variant embodiment of the above, electronic components of the powersupply module may be disposed on the light strip by a method ofembedding or inserting, e.g. by embedding the components onto a bendableor flexible light strip. In some embodiments, this embedding may berealized by a method using copper-clad laminates (CCL) for forming aresistor or capacitor; a method using ink related to silkscreenprinting; or a method of ink jet printing to embed passive components,wherein an ink jet printer is used to directly print inks to constitutepassive components and related functionalities to intended positions onthe light strip. Then through treatment by ultraviolet (UV) light ordrying/sintering, the light strip is formed where passive components areembedded. The electronic components embedded onto the light stripinclude for example resistors, capacitors, and inductors. In otherembodiments, active components also may be embedded. Through embeddingsome components onto the light strip, a reasonable layout of the powersupply module can be achieved to allow of an improved design in the endcap(s), because the surface area on a printed circuit board used forcarrying components of the power supply module is reduced or smaller,and as a result the size, weight, and thickness of the resulting printedcircuit board for carrying components of the power supply module is alsosmaller or reduced. Also in this situation since welding points on theprinted circuit board for welding resistors and/or capacitors if theywere not to be disposed on the light strip are no longer used, thereliability of the power supply module is improved, in view of the factthat these welding points are most liable to (cause or incur) faults,malfunctions, or failures. Further, the length of conductive linesneeded for connecting components on the printed circuit board istherefore also reduced, which allows of a more compact layout ofcomponents on the printed circuit board and thus improving thefunctionalities of these components.

Next, methods to produce embedded capacitors and resistors are explainedas follows.

Usually, methods for manufacturing embedded capacitors employ or involvea concept called distributed or planar capacitance. The manufacturingprocess may include the following step(s). On a substrate of a copperlayer a very thin insulation layer is applied or pressed, which is thengenerally disposed between a pair of layers including a power conductivelayer and a ground layer. The very thin insulation layer makes thedistance between the power conductive layer and the ground layer veryshort. A capacitance resulting from this structure can also be realizedby a conventional technique of a plated-through hole. Basically, thisstep is used to create this structure comprising a big parallel-platecapacitor on a circuit substrate.

Of products of high electrical capacity, certain types of productsemploy distributed capacitances, and other types of products employseparate embedded capacitances. Through putting or adding a highdielectric-constant material such as barium titanate into the insulationlayer, the high electrical capacity is achieved.

A usual method for manufacturing embedded resistors employ conductive orresistive adhesive. This may include, for example, a resin to whichconductive carbon or graphite is added, which may be used as an additiveor filler. The additive resin is silkscreen printed to an objectlocation, and is then after treatment laminated inside the circuitboard. The resulting resistor is connected to other electroniccomponents through plated-through holes or microvias. Another method iscalled Ohmega-Ply, by which a two metallic layer structure of a copperlayer and a thin nickel alloy layer constitutes a layer resistorrelative to a substrate. Then through etching the copper layer andnickel alloy layer, different types of nickel alloy resistors withcopper terminals can be formed. These types of resistor are eachlaminated inside the circuit board.

In an embodiment, conductive wires/lines are directly printed in alinear layout on an inner surface of the LED glass lamp tube, with LEDcomponents directly attached on the inner surface and electricallyconnected by the conductive wires. In some embodiments, the LEDcomponents in the form of chips are directly attached over theconductive wires on the inner surface, and connective points are atterminals of the wires for connecting the LED components and the powersupply module. After being attached, the LED chips may have fluorescentpowder applied or dropped thereon, for producing white light or light ofother color by the operating LED tube lamp.

In some embodiments, luminous efficacy of the LED or LED component is 80lm/W or above, and in some embodiments, it may be 120 lm/W or above.Certain more optimal embodiments may include a luminous efficacy of theLED or LED component of 160 lm/W or above. White light emitted by an LEDcomponent may be produced, for example, by mixing fluorescent powderwith the monochromatic light emitted by a monochromatic LED chip. Thewhite light in its spectrum has major wavelength ranges of 430-460 nmand 550-560 nm, or major wavelength ranges of 430-460 nm, 540-560 nm,and 620-640 nm.

FIG. 32A is a block diagram of using a power supply module in an LEDlamp according to one embodiment. The embodiment of FIG. 32A includesrectifying circuits 510 and 540, and a filtering circuit 520, andfurther includes an anti-flickering circuit 550 coupled betweenfiltering circuit 520 and an LED lighting module 530. It's noted thatrectifying circuit 540 may be omitted and is thus depicted in a dottedline in FIG. 32A.

Anti-flickering circuit 550 is coupled to filtering output terminals 521and 522, to receive a filtered signal, and under specific circumstancesto consume partial energy of the filtered signal so as to reduce (theincidence of) ripples of the filtered signal disrupting or interruptingthe light emission of the LED lighting module 530. In general, filteringcircuit 520 has such filtering components as resistor(s) and/orinductor(s), and/or parasitic capacitors and inductors, which may formresonant circuits. Upon breakoff or stop of an AC power signal, as whenthe power supply of the LED lamp is turned off by a user, theamplitude(s) of resonant signals in the resonant circuits will decreasewith time. But LEDs in the LED module of the LED lamp are unidirectionalconduction devices and require a minimum conduction voltage for the LEDmodule. When a resonant signal's trough value is lower than the minimumconduction voltage of the LED module, but its peak value is still higherthan the minimum conduction voltage, the flickering phenomenon willoccur in light emission of the LED module. In this case anti-flickeringcircuit 550 works by allowing a current matching a defined flickeringcurrent value of the LED component to flow through, consuming partialenergy of the filtered signal which should be higher than the energydifference of the resonant signal between its peak and trough values, soas to reduce the flickering phenomenon. In certain embodiments, apreferred occasion for anti-flickering circuit 550 to work is when thefiltered signal's voltage approaches (and is still higher than) theminimum conduction voltage.

In some embodiments, anti-flickering circuit 550 may be more suitablefor the situation in which LED lighting module 530 doesn't include adriving circuit, for example, when LED module 630 of LED lighting module530 is directly driven to emit light by a filtered signal from afiltering circuit. In this case, the light emission of LED module 630will directly reflect variation in the filtered signal due to itsripples. In this situation, the introduction of anti-flickering circuit550 will help prevent the flickering phenomenon from occurring in theLED lamp upon the breakoff of power supply to the LED lamp.

FIG. 32B is a schematic diagram of the anti-flickering circuit accordingto an embodiment of the present invention. Referring to FIG. 32B,anti-flickering circuit 650 includes at least a resistor, such as tworesistors connected in series between filtering output terminals 521 and522. In this embodiment, anti-flickering circuit 650 in use consumespartial energy of a filtered signal continually. When in normaloperation of the LED lamp, this partial energy is far lower than theenergy consumed by LED lighting module 530. But upon a breakoff or stopof the power supply, when the voltage level of the filtered signaldecreases to approach the minimum conduction voltage of LED module 630,this partial energy is still consumed by anti-flickering circuit 650 inorder to offset the impact of the resonant signals which may cause theflickering of light emission of LED module 630. In some embodiments, acurrent equal to or larger than an anti-flickering current level may beset to flow through anti-flickering circuit 650 when LED module 630 issupplied by the minimum conduction voltage, and then an equivalentanti-flickering resistance of anti-flickering circuit 650 can bedetermined based on the set current.

FIG. 33A is a block diagram including a power supply module for an LEDtube lamp according to an embodiment of the present invention. Comparedto that shown in FIG. 28E, the present embodiment comprises therectifying circuits 510 and 540, the filtering circuit 520, and the LEDlighting module 530, and further comprises two filament-simulatingcircuits 1560. The filament-simulating circuits 1560 are respectivelycoupled between the pins 501 and 502 and coupled between the pins 503and 504, for improving a compatibility with a lamp driving circuithaving filament detection function, e.g.: program-start ballast.

In an initial stage upon the lamp driving circuit having filamentdetection function being activated, the lamp driving circuit willdetermine whether the filaments of the lamp operate normally or are inan abnormal condition of short-circuit or open-circuit. When determiningthe abnormal condition of the filaments, the lamp driving circuit stopsoperating and enters a protection state. In order to avoid that the lampdriving circuit erroneously determines the LED tube lamp to be abnormaldue to the LED tube lamp having no filament, the two filament-simulatingcircuits 1560 simulate the operation of actual filaments of afluorescent tube to have the lamp driving circuit enter into a normalstate to start the LED lamp normally.

FIG. 33B is a schematic diagram of a filament-simulating circuitaccording to one embodiment. The filament-simulating circuit comprises acapacitor 1663 and a resistor 1665 connected in parallel, and two endsof the capacitor 1663 and two ends of the resistor 1665 are rerespectively coupled to filament simulating terminals 1661 and 1662.Referring to FIG. 33A, the filament simulating terminals 1661 and 1662of the two filament simulating 1660 are respectively coupled to the pins501 and 502 and the pins 503 and 504. During the filament detectionprocess, the lamp driving circuit outputs a detection signal to detectthe state of the filaments. The detection signal passes the capacitor1663 and the resistor 1665 and so the lamp driving circuit determinesthat the filaments of the LED lamp are normal.

In addition, a capacitance value of the capacitor 1663 is low and so acapacitive reactance (equivalent impedance) of the capacitor 1663 is farlower than an impedance of the resistor 1665 due to the lamp drivingcircuit outputting a high-frequency alternative current (AC) signal todrive LED lamp. Therefore, the filament-simulating circuit 1660 consumesfairly low power when the LED lamp operates normally, and so it almostdoes not affect the luminous efficiency of the LED lamp.

FIG. 33C is a schematic block diagram including a filament-simulatingcircuit according to one embodiment. In the present embodiment, thefilament-simulating circuit 1660 replaces the terminal adapter circuit541 of the rectifying circuit 810 shown in FIG. 29C, which is adopted asthe rectifying circuit 510 or/and 540 in the LED lamp. For example, thefilament-simulating circuit 1660 of the present embodiment has both offilament simulating and terminal adapting functions. Referring to FIG.33A, the filament simulating terminals 1661 and 1662 of thefilament-simulating circuit 1660 are respectively coupled to the pins501 and 502 or/and pins 503 and 504. The half-wave node 819 ofrectifying unit 815 in the rectifying circuit 810 is coupled to thefilament simulating terminal 1662.

FIG. 33D is a schematic block diagram including a filament-simulatingcircuit according to another embodiment. Compared to that shown in FIG.33C, the half-wave node is changed to be coupled to the filamentsimulating terminal 1661, and the filament-simulating circuit 1660 inthe present embodiment still has both of filament simulating andterminal adapting functions.

FIG. 33E is a schematic diagram of a filament-simulating circuitaccording to another embodiment. A filament-simulating circuit 1760comprises capacitors 1763 and 1764, and the resistors 1765 and 1766. Thecapacitors 1763 and 1764 are connected in series and coupled between thefilament simulating terminals 1661 and 1662. The resistors 1765 and 1766are connected in series and coupled between the filament simulatingterminals 1661 and 1662. Furthermore, the connection node of capacitors1763 and 1764 is coupled to that of the resistors 1765 and 1766.Referring to FIG. 33A, the filament simulating terminals 1661 and 1662of the filament-simulating circuit 1760 are respectively coupled to thepins 501 and 502 and the pins 503 and 504. When the lamp driving circuitoutputs the detection signal for detecting the state of the filament,the detection signal passes the capacitors 1763 and 1764 and theresistors 1765 and 1766 so that the lamp driving circuit determines thatthe filaments of the LED lamp are normal.

In some embodiments, capacitance values of the capacitors 1763 and 1764are low and so a capacitive reactance of the serially connectedcapacitors 1763 and 1764 is far lower than an impedance of the seriallyconnected resistors 1765 and 1766 due to the lamp driving circuitoutputting the high-frequency AC signal to drive the LED lamp.Therefore, the filament-simulating circuit 1760 consumes fairly lowpower when the LED lamp operates normally, and so it almost does notaffect the luminous efficiency of the LED lamp. Moreover, any one of thecapacitor 1763 and the resistor 1765 is short circuited or is an opencircuit, or any one of the capacitor 1764 and the resistor 1766 is shortcircuited or is an open circuit, the detection signal still passesthrough the filament-simulating circuit 1760 between the filamentsimulating terminals 1661 and 1662. Therefore, the filament-simulatingcircuit 1760 still operates normally when any one of the capacitor 1763and the resistor 1765 is short circuited or is an open circuit or anyone of the capacitor 1764 and the resistor 1766 is short circuited or isan open circuit, and so it has quite high fault tolerance.

FIG. 33F is a schematic block diagram including a filament-simulatingcircuit according to one embodiment. In the present embodiment, thefilament-simulating circuit 1860 replaces the terminal adapter circuit541 of the rectifying circuit 810 shown in FIG. 29C, which is adopted asthe rectifying circuit 510 or/and 540 in the LED lamp. For example, thefilament-simulating circuit 1860 of the present embodiment has both offilament simulating and terminal adapting functions. An impedance of thefilament-simulating circuit 1860 has a negative temperature coefficient(NTC), i.e., the impedance at a higher temperature is lower than that ata lower temperature. In the present embodiment, the filament-simulatingcircuit 1860 comprises two NTC resistors 1863 and 1864 connected inseries and coupled to the filament simulating terminals 1661 and 1662.Referring to FIG. 33A, the filament simulating terminals 1661 and 1662are respectively coupled to the pins 501 and 502 or/and the pins 503 and504. The half-wave node 819 of the rectifying unit 815 in the rectifyingcircuit 810 is coupled to a connection node of the NTC resistors 1863and 1864.

When the lamp driving circuit outputs the detection signal for detectingthe state of the filament, the detection signal passes the NTC resistors1863 and 1864 so that the lamp driving circuit determines that thefilaments of the LED lamp are normal. The impedance of the seriallyconnected NTC resistors 1863 and 1864 is gradually decreased with thegradually increasing of temperature due to the detection signal or apreheat process. When the lamp driving circuit enters into the normalstate to start the LED lamp normally, the impedance of the seriallyconnected NTC resistors 1863 and 1864 is decreased to a relative lowvalue and so the power consumption of the filament simulation circuit1860 is lower.

An exemplary impedance of the filament-simulating circuit 1860 can be 10ohms or more at room temperature (25 degrees Celsius) and may bedecreased to a range of about 2-10 ohms when the lamp driving circuitenters into the normal state. It may be preferred that the impedance ofthe filament-simulating circuit 1860 is decreased to a range of about3-6 ohms when the lamp driving circuit enters into the normal state.

FIG. 34A is a block diagram including a power supply module for an LEDtube lamp according to one embodiment. Compared to that shown in FIG.28E, the present embodiment comprises the rectifying circuits 510 and540, the filtering circuit 520, and the LED lighting module 530, andfurther comprises an over voltage protection (OVP) circuit 1570. The OVPcircuit 1570 is coupled to the filtering output terminals 521 and 522for detecting the filtered signal. The OVP circuit 1570 clamps the levelof the filtered signal when determining the level thereof higher than adefined, particular OVP value. Hence, the OVP circuit 1570 protects theLED lighting module 530 from damage due to an OVP condition. Therectifying circuit 540 may be omitted and is therefore depicted by adotted line.

FIG. 34B is a schematic diagram of an overvoltage protection (OVP)circuit according to one embodiment. The OVP circuit 1670 comprises avoltage clamping diode 1671, such as zener diode, coupled to thefiltering output terminals 521 and 522. The voltage clamping diode 1671is conducted to clamp a voltage difference at a breakdown voltage whenthe voltage difference of the filtering output terminals 521 and 522(i.e., the level of the filtered signal) reaches the breakdown voltage.The breakdown voltage may be preferred in a range of about 40 V to about100 V, and more preferred in a range of about 55 V to about 75V.Referring to FIG. 24, in one embodiment, each of the LED light sources202 may be provided with a LED lead frame 202 b having a recess 202 a,and an LED chip 18 disposed in the recess 202 a. The recess 202 a may beone or more than one in amount. The recess 202 a may be filled withphosphor covering the LED chip 18 to convert emitted light therefrominto a desired light color. Compared with a conventional LED chip beinga substantial square, the LED chip 18 in this embodiment is in someembodiments rectangular with the dimension of the length side to thewidth side at a ratio ranges generally from about 2:1 to about 10:1, insome embodiments from about 2.5:1 to about 5:1, and in some moredesirable embodiments from 3:1 to 4.5:1. Moreover, the LED chip 18 is insome embodiments arranged with its length direction extending along thelength direction of the glass tube 1 to increase the average currentdensity of the LED chip 18 and improve the overall illumination fieldshape of the glass tube 1. The glass tube 1 may have a number of LEDlight sources 202 arranged into one or more rows, and each row of theLED light sources 202 is arranged along the length direction(Y-direction) of the glass tube 1.

Referring again to FIG. 24, the recess 202 a is enclosed by two parallelfirst sidewalls 15 and two parallel second sidewalls 16 with the firstsidewalls 15 being lower than the second sidewalls 16. The two firstsidewalls 15 are arranged to be located along a length direction(Y-direction) of the glass tube 1 and extend along the width direction(X-direction) of the glass tube 1, and two second sidewalls 16 arearranged to be located along a width direction (X-direction) of theglass tube 1 and extend along the length direction (Y-direction) of theglass tube 1. The extending direction of the first sidewalls 15 may besubstantially or exactly parallel to the width direction (X-direction)of the glass tube 1, and the first sidewalls may have various outlinessuch as zigzag, curved, wavy, and the like. Similarly, the extendingdirection of the second sidewalls 16 may be substantially or exactlyparallel to the length direction (Y-direction) of the glass tube 1, andthe second sidewalls may have various outlines such as zigzag, curved,wavy, and the like. In one row of the LED light sources 202, thearrangement of the first sidewalls 15 and the second sidewalls 16 foreach LED light source 202 can be the same or different.

Having the first sidewalls 15 being lower than the second sidewalls 16and proper distance arrangement, the LED lead frame 202 b allowsdispersion of the light illumination to cross over the LED lead frame202 b without causing uncomfortable visual feeling to people observingthe LED tube lamp along the Y-direction. The first sidewalls 15 may tobe lower than the second sidewalls, however, and in this case each rowsof the LED light sources 202 are more closely arranged to reduce grainyeffects. On the other hand, when a user of the LED tube lamp observesthe glass tube thereof along the X-direction, the second sidewalls 16also can block user's line of sight from seeing the LED light sources202, and which reduces unpleasing grainy effects.

Referring again to FIG. 24, the first sidewalls 15 each includes aninner surface 15 a facing toward outside of the recess 202 a. The innersurface 15 a may be designed to be an inclined plane such that the lightillumination easily crosses over the first sidewalls 15 and spreads out.The inclined plane of the inner surface 15 a may be flat or cambered orcombined shape. In some embodiments, when the inclined plane is flat,the slope of the inner surface 15 a ranges from about 30 degrees toabout 60 degrees. Thus, an included angle between the bottom surface ofthe recess 202 a and the inner surface 15 a may range from about 120 toabout 150 degrees. In some embodiments, the slope of the inner surface15 a ranges from about 15 degrees to about 75 degrees, and the includedangle between the bottom surface of the recess 202 a and the innersurface 15 a ranges from about 105 degrees to about 165 degrees.

There may be one row or several rows of the LED light sources 202arranged in a length direction (Y-direction) of the glass tube 1. Incase of one row, in one embodiment the second sidewalls 16 of the LEDlead frames 202 b of all of the LED light sources 202 located in thesame row are disposed in same straight lines to respectively from twowalls for blocking user's line of sight seeing the LED light sources202. In case of several rows, in one embodiment only the LED lead frames202 b of the LED light sources 202 disposed in the outermost two rowsare disposed in same straight lines to respectively form walls forblocking user's line of sight seeing the LED light sources 202. The LEDlead frames 202 b of the LED light sources 202 disposed in the otherrows can have different arrangements. For example, as far as the LEDlight sources 202 located in the middle row (third row) are concerned,the LED lead frames 202 b thereof may be arranged such that: each LEDlead frame 202 b has the first sidewalls 15 arranged along the lengthdirection (Y-direction) of the glass tube 1 with the second sidewalls 16arranged along in the width direction (X-direction) of the glass tube 1;each LED lead frame 202 b has the first sidewalls 15 arranged along thewidth direction (X-direction) of the glass tube 1 with the secondsidewalls 16 arranged along the length direction (Y-direction) of theglass tube 1; or the LED lead frames 202 b are arranged in a staggeredmanner. To reduce grainy effects caused by the LED light sources 202when a user of the LED tube lamp observes the glass tube thereof alongthe X-direction, it may be enough to have the second sidewalls 16 of theLED lead frames 202 b of the LED light sources 202 located in theoutmost rows to block user's line of sight from seeing the LED lightsources 202. Different arrangements may be used for the second sidewalls16 of the LED lead frames 202 b of one or several of the LED lightsources 202 located in the outmost two rows.

In summary, when a plurality of the LED light sources 202 are arrangedin a row extending along the length direction of the glass tube 1, thesecond sidewalls 16 of the LED lead frames 202 b of all of the LED lightsources 202 located in the same row may be disposed in same straightlines to respectively form walls for blocking user's line of sightseeing the LED light sources 202. When a plurality of the LED lightsources 202 are arranged in a number of rows being located along thewidth direction of the glass tube 1 and extending along the lengthdirection of the glass tube 1, the second sidewalls 16 of the LED leadframes 202 b of all of the LED light sources 202 located in the outmosttwo rows may be disposed in straight lines to respectively from twowalls for blocking user's line of sight seeing the LED light sources202. The one or more than one rows located between the outmost rows mayhave the first sidewalls 15 and the second sidewalls 16 arranged in away the same as or different from that for the outmost rows.

Turing to FIG. 27, in accordance with an exemplary embodiment, the endcap 3 includes a housing, an electrically conductive pin 301, a powersupply 5 and a safety switch. The safety switch is positioned betweenthe electrically conductive pin 301 and the power supply 5. The safetyswitch may further include a micro switch 334 and an actuator 332. Theend caps 3 are disposed on two ends of the glass tube 1 and areconfigured to turn on the safety switch—and make a circuit connecting,sequentially, main electricity coming from a socket of a lamp holder,the electrically conductive pin 301, the power supply 5 and the LEDlight assembly—when the electrically conductive pin 301 is plugged intothe socket. The end cap 3 is configured to turn off the safety switchand open the circuit when the electrically conductive pin 301 isunplugged from the socket of the lamp holder. The glass tube 1 is thusconfigured to minimize risk of electric shocks during installation andto comply with safety regulations.

In some embodiments, the safety switch directly—andmechanically—completes and breaks the circuit of the LED tube lamp. Inother embodiments, the safe switch controls another electrical circuit,i.e. a relay, which in turn completes and breaks the circuit of the LEDtube lamp. Some relays use an electromagnet to operate a switchingmechanism mechanically, but other operating principles are also used.For example, solid-state relays control power circuits with no movingparts, instead using a semiconductor device to perform switching.

As shown in FIG. 27, the proportion of the end cap 3 in relation to theglass tube 1 is exaggerated in order to highlight the structure of theend cap 3. In an embodiment, the depth of the end cap 3 is from 9 to 70mm. The axial length of the glass tube 1 is from 254 to 2000 mm, i.e.from 1 inch to 8 inch.

The safety switch may be two in number and disposed respectively insidetwo end caps. In an embodiment, a first end cap of the lamp tubeincludes a safety switch but a second end cap does not, and a warning isattached to the first end cap to alert an operator to plug in the secondend cap before moving on to the first end cap.

In an embodiment, the safety switch may be a level switch includingliquid. Only when liquid inside the level switch is made to flow to adesignated place, the level switch is turned on. The end cap 3 isconfigured to turn on the level switch and, directly or through a relay,complete or close the circuit only when the electrically conductive pin301 is plugged into the socket. Alternatively, a micro switch istriggered by an actuator when the electrically conductive pin is pluggedinto the socket and the actuator is pressed. The end cap 3 is configuredto, likewise, turn on the micro switch and, directly or through a relay,close the circuit only when the electrically conductive pin 301 isplugged into the socket.

Turning to FIG. 26A, in accordance with an exemplary embodiment, the endcap 3 includes a housing 300, an electrically conductive pin 301disposed on top wall of the housing 300, an actuator 332 movablydisposed on the housing 300 along the direction of the electricallyconductive pin 301, and a micro switch 334. The upper portion of theactuator 332 projects out of an opening formed in the top wall of thehousing 300. The actuator 332 includes, for example, inside the housing300, a stopping flange 337 extending radially at the actuator'sintermediary portion and a shaft 335 extending axially at the actuator'slower portion. The shaft 335 is movably connected to a base 336 rigidlymounted inside the housing 300. A preloaded coil spring 333 is retained,around the shaft 335, between the stopping flange 337 and the base 336.An aperture is provided in the upper portion of the actuator 332 throughwhich the electrically conductive pin 301 is arranged. The micro switch334 is positioned inside the housing 300 to be actuated by the shaft 335at a predetermined actuation point. The micro switch 334, when actuated(e.g., when moved in a direction away from the top wall of the housing300, closes the circuit, directly or through a relay, between theelectrically conductive pin 301 and the power supply 5. The actuator 332is aligned with the electrically conductive pin 301, the opening in thetop wall of the housing 300, and the coil spring 333 along thelongitudinal axis of the glass tube 1, to be reciprocally movablebetween the top wall of the housing 300 and the base 336. When theelectrically conductive pin 301 is unplugged from the socket of a lampholder, the coil spring 333 and stopping flange 337 biases (e.g., moves)the actuator 332 to its rest position. The micro switch 334 then staysoff and the circuit of the LED tube lamp stays open. When theelectrically conductive pin 301 is duly plugged into the socket, theactuator 332 is depressed and brings the shaft 335 to the actuationpoint. The micro switch 334 is turned on to, directly or through arelay, complete the circuit of the LED tube lamp.

Turning to FIG. 26B, in accordance with an exemplary embodiment, the endcap 3 includes a housing 300, an electrically conductive pin 301 adisposed on top wall of the housing 300, an actuator 332 movablydisposed on the housing 300 along the direction of the electricallyconductive pin 301 a, and a micro switch 334. In one embodiment, theelectrically conductive pin 301 a is an enlarged hollow structure. Theupper portion of the actuator 332 is bowl-shaped to receive theelectrically conductive pin 301 a and projects out of an opening formedin the top wall of the housing 300. The actuator 332 includes, insidethe housing 300, a stopping flange 337 extending radially at theactuator's intermediary portion and, at the actuator's lower portion, aspring retainer 337 a and a bulging part 338 (also referred to as aprotruding portion or a protrusion, protruding from a bottom of theactuator 332 or a spring retainer 337 a of the actuator 332). Apreloaded coil spring 333 is retained between the string retainer and abase 336 rigidly mounted inside the housing 300. The micro switch 334 ispositioned inside the housing 300 to be actuated by the bulging part 338at a predetermined actuation point. The micro switch 334, when actuated,completes the circuit, directly or through a relay, between theelectrically conductive pin 301 a and the power supply. The actuator 332is aligned with the electrically conductive pin 301 a, the opening inthe top wall of the housing 300 and the coil spring 333 along thelongitudinal axis of the lamp tube 1 to be reciprocally movable betweenthe top wall of the housing 300 and the base 336. When the electricallyconductive pin 301 a is unplugged from the socket of a lamp holder, thecoil spring 333 and the stopping flange 337 biases the actuator 332 toits rest position. The micro switch 334 stays off and the circuit of theLED tube lamp 1 stays open. When the electrically conductive pin 301 ais duly plugged into the socket of the lamp holder, the actuator 332 isdepressed and brings the bulging part 338 to the actuation point. Themicro switch 334 is turned on to, directly or through a relay, completethe circuit.

Turning to FIG. 26C, in accordance with an exemplary embodiment, the endcap 3 includes a housing 300, a power supply (not shown), anelectrically conductive pin 301 disposed on top wall of the housing 300,an actuator 332 movably disposed on the housing 300 along the directionof the electrically conductive pin 301, and a micro switch 334. In oneembodiment, the end cap includes a pair of electrically conductive pins301. The upper portion of the actuator 332 projects out of an openingformed in the top wall of the housing 300. The actuator 332 includes,inside the housing 300, a stopping flange 337 extending radially at theactuator's intermediary portion and a spring retainer at the actuator'slower portion. A first coil spring 333 a, preloaded, is retained betweena spring retainer and a first end of the micro switch 334. A second coilspring 333 b, also preloaded, is retained between a second end of themicro switch 334 and a base rigidly mounted inside the housing. Both ofthe springs 333 a, 333 b are chosen to respond to a gentle depression;however, in certain embodiments, the first coil spring 333 a is chosento have a different stiffness than the second coil spring 333 b. Forexample, in one embodiment, the first coil spring 333 a reacts to adepression of from 0.5 to 1 N but the second coil spring 333 b reacts toa depression of from 3 to 4 N (e.g., the second coil spring 333 b may bestiffer than the first coil spring 333 a, and may require a force of 3to 8 times the force used to move the first coil spring 333 a). Theactuator 332 is aligned with the opening in the top wall of the housing300, the micro switch 334, and the set of coil springs 333 a, 333 balong the longitudinal axis of the lamp tube, to be reciprocally movablebetween the top wall of the housing 300 and the base. The micro switch334, sandwiched between the first coil spring 333 a and the second coilspring 333 b, is actuated when the first coil spring 333 a is compressedto a predetermined actuation point. The micro switch 334, when actuated,completes the circuit, directly or through a relay, between the pair ofelectrically conductive pins 301 and the power supply. When the pair ofelectrically conductive pins 301 are unplugged from the socket of a lampholder, the pair of coil springs 333 a, 333 b and the stopping flange337 bias the actuator 332 to its rest position. The micro switch 334stays off and the circuit of the LED tube lamp stays open. When the pairof electrically conductive pins 301 are duly plugged into the socket ofa lamp holder, the actuator 332 is depressed and compresses the firstcoil spring 333 a to the actuation point. The micro switch 334 is turnedon to, directly or through a relay, complete the circuit.

Turning to FIG. 26D, in accordance with an exemplary embodiment, the endcap 3 includes a housing 300, a power supply (not shown), anelectrically conductive pin 301 disposed on top wall of the housing 300,an actuator 332 movably disposed on the housing 300 along the directionof the electrically conductive pin 301, a first contact element 334 aand a second contact element 338. The upper portion of the actuator 332projects out of an opening formed in the top wall of the housing 300.The actuator 332 includes, inside the housing 300, a stopping flangeextending radially at the actuator's intermediary portion and a shaft335 extending axially at the actuator's lower portion. The shaft 335 ismovably connected to a base 336 rigidly mounted inside the housing 300.A preloaded coil spring 333 is retained, around the shaft 335, betweenthe stopping flange and the base 336. An aperture is provided in theupper portion of the actuator 332 through which the electricallyconductive pin 301 is arranged. The actuator 332 is aligned with theelectrically conductive pin 301, the opening in the top wall of thehousing 300, the coil spring 333 and the first and second contactelements 334 a, 338 along the longitudinal axis of the lamp tube to bereciprocally movable between the top wall of the housing 300 and thebase 336. The first contact element 334 a includes a plurality ofmetallic pieces, which are spaced apart from one another, and isconfigured to form a flexible female-type receptacle, e.g. V-shaped orbell-shaped. The second contact element 338 is positioned on the shaft335 to, when the shaft 335 moves downwards, come into the first contactelement 334 a and electrically connect the plurality of metallic piecesat a predetermined actuation point. The first contact element 334 a isconfigured to impart a spring-like bias on the second contact element338 when the second contact element 338 goes into the first contactelement 334 a to ensure faithful electrical conduction between the two.The first and second contact elements 334 a, 338 are made from, forexample, copper alloy. When the electrically conductive pin 301 isunplugged from the socket of a lamp holder, the coil spring 333 and thestopping flange biases the actuator 332 to its rest position. The firstand second contact elements 334 a, 338 stay unconnected and the circuitof the LED tube lamp stays open. When the electrically conductive pin301 is duly plugged into the socket of a lamp holder, the actuator 332is depressed and brings the second contact element 338 to the actuationpoint. The first and second contact elements 334 a, 338 are connectedto, directly or through a relay, complete the circuit of the LED tubelamp. The contact element 334 a may be made of copper.

Turning to FIG. 26E, in accordance with an exemplary embodiment, the endcap 3 includes a housing 300, a power supply 5, an electricallyconductive pin 301 disposed on top wall of the housing 300, an actuator332 movably disposed on the housing 300 along the direction of theelectrically conductive pin 301, a first contact element 334 a and asecond contact element. The upper portion of the actuator 332 projectsout of an opening formed in the top wall of the housing 300. Theactuator 332 includes, inside the housing 300, a stopping flange (notshown) extending radially at the actuator's intermediary portion and ashaft 335 extending axially at the actuator's lower portion. The shaft335 is movably connected to a base (not shown) rigidly mounted insidethe housing 300. A preloaded coil spring 333 is retained, around theshaft 335, between the stopping flange and the base. The actuator 332 isaligned with the opening in the top wall of the housing 300, the coilspring 333, the first contact element 334 a and the second contactelement along the longitudinal axis of the lamp tube to be reciprocallymovable between the top wall of the housing 300 and the base. The firstcontact element 334 a forms an integral and flexible female-typereceptacle and may be made, for example from a metal such as copperand/or copper alloy. The second contact element, made from, for example,copper and/or copper alloy, is fixedly disposed inside the housing 300.In an embodiment, the second contact element is fixedly disposed on thepower supply 5. The first contact element 334 a is attached to the lowerend of the shaft 335 to, when the shaft 335 moves downwards, receive andelectrically connect the second contact element at a predeterminedactuation point. The first contact element 334 a is configured to imparta spring-like bias on the second contact element when the formerreceives the latter to ensure faithful electrically conductive with eachother. When the electrically conductive pin 301 is unplugged from thesocket of a lamp holder, the coil spring 333 and the stopping flangebiases the actuator 332 to its rest position. The first contact element334 a and the second contact element stay unconnected and the circuit ofthe LED tube lamp stays open. When the electrically conductive pin 301is duly plugged into the socket of a lamp holder, the actuator 332 isdepressed and brings the first contact element 334 a to the actuationpoint. The first contact element 334 a and the second contact elementare connected to, directly or through a relay, complete the circuit ofthe LED tube lamp.

Turning to FIG. 26F, in accordance with an exemplary embodiment of theclaimed invention, the end cap 3 includes a housing 300, a power supply5, an electrically conductive pin 301 disposed on top wall of thehousing 300, an actuator 332 movably disposed on the housing 300 alongthe direction of the electrically conductive pin 301, a first contactelement 334 b and a second contact element. The upper portion of theactuator 332 projects out of an opening formed in the top wall of thehousing 300. The actuator 332 includes, inside the housing 300, astopping flange (not shown) extending radially at the actuator'sintermediary portion and a shaft 335 extending axially at the actuator'slower portion. The shaft 335 is movably connected to a base rigidlymounted inside the housing 300. A preloaded coil spring 333 is retained,around the shaft 335, between the stopping flange and the base. Theactuator 332 is aligned with the opening in the top wall of the housing300, the coil spring 333, the first contact element 334 b, and thesecond contact element along the longitudinal axis of the lamp tube, tobe reciprocally movable between the top wall of the housing 300 and thebase. In one embodiment, the shaft 335 includes a non-electricallyconductive body in the shape of an elongated thin plank and a window 339carved out from the body. The first contact element 334 b and the secondcontact element are fixedly disposed inside the housing 300 and faceeach other through the shaft 335. The first contact element 334 b isconfigured to impart a spring-like bias on the shaft 335 and to push theshaft 335 against the second contact element. In one embodiment, thefirst contact element 334 b is a bow-shaped laminate bending towards theshaft 335 and the second contact element, which is disposed on the powersupply 5. The first contact element 334 b and the second contact elementare made from, for example, copper and/or copper alloy. When theactuator 332 is in its rest position, the first contact element 334 band the second contact element are prevented by the body of the shaft335 from engaging each other. However, the first contact element 334 bis configured to, when the shaft brings its window 339 downwards to apredetermined actuation point, engage and electrically connect thesecond contact element through the window 339. When the electricallyconductive pin 301 is unplugged from the socket, the coil spring 333 andthe stopping flange biases the actuator 332 to its rest position. Thefirst contact element 334 b and the second contact element stayunconnected and the circuit of the LED tube lamp stays open. When theelectrically conductive pin 301 is duly plugged into the socket of alamp holder, the actuator 332 is depressed and brings the window 339 tothe actuation point. The first contact element 334 b engages the secondcontact element to, directly or through a relay, complete the circuit ofthe LED tube lamp.

In an embodiment, the upper portion of the actuator 332 that projectsout of the housing 300 has a shorter length than the electricallyconductive pin 301. In some embodiments, the projected portion of theactuator 332 has a length of from 20 to 95% of that of the electricallyconductive pin 301.

The various systems shown in FIGS. 26A through 26F that allow anactuator to move toward and extend away from a LED tube and a housing ofthe end cap may be referred to herein as expansion means. An expandablecomponent, such as actuator at an end of the housing of the end cap, canbe used to change an overall length of at least part of the LED tubelamp (e.g., a part extending along a central radial axis of the LED tubelamp). Also, though a coil spring is specifically described above, othertypes of springs or devices that function as a spring can be used.

The LED tube lamps according to various different embodiments aredescribed as above. With respect to an entire LED tube lamp, thefeatures including “securing the glass tube and the end cap with ahighly thermal conductive silicone gel”, “covering the glass tube with aheat shrink sleeve”, “adopting the bendable circuit sheet as the LEDlight strip”, “the bendable circuit sheet being a metal layer structureor a double layer structure of a metal layer and a dielectric layer”,“coating the adhesive film on the inner surface of the glass tube”,“coating the diffusion film on the inner surface of the glass tube”,“covering the diffusion film in form of a sheet above the LED lightsources”, “coating the reflective film on the inner surface of the glasstube”, “the end cap including the thermal conductive member”, “the endcap including the magnetic metal member”, “the LED light source beingprovided with the lead frame”, “utilizing the circuit board assembly toconnect the LED light strip and the power supply”, “the rectifyingcircuit”, “the terminal adapter circuit”, “the anti-flickering circuit”,“the protection circuit” and “the filament-simulating circuit” may beapplied in practice singly or integrally such that only one of thefeatures is practiced or a number of the features are simultaneouslypracticed.

Furthermore, any of the features “adopting the bendable circuit sheet asthe LED light strip”, “the bendable circuit sheet being a metal layerstructure or a double layer structure of a metal layer and a dielectriclayer” which concerns the “securing the glass tube and the end cap witha highly thermal conductive silicone gel” includes any related technicalpoints and their variations and any combination thereof as described inthe above-mentioned embodiments of the present invention, and whichconcerns the “covering the glass tube with a heat shrink sleeve”includes any related technical points and their variations and anycombination thereof as described in the above-mentioned embodiments.“coating the adhesive film on the inner surface of the glass tube”,“coating the diffusion film on the inner surface of the glass tube”,“covering the diffusion film in form of a sheet above the LED lightsources”, “coating the reflective film on the inner surface of the glasstube”, “the LED light source being provided with the lead frame”, and“utilizing the circuit board assembly to connect the LED light strip andthe power supply” includes any related technical points and theirvariations and any combination thereof as described in theabovementioned embodiments.

As an example, the feature “adopting the bendable circuit sheet as theLED light strip” may include “the connection between the bendablecircuit sheet and the power supply is by way of wire bonding orsoldering bonding; the bendable circuit sheet being a metal layerstructure or a double layer structure of a metal layer and a dielectriclayer; the bendable circuit sheet has a circuit protective layer made ofink to reflect lights and has widened part along the circumferentialdirection of the glass tube to function as a reflective film.”

As an example, the feature “coating the diffusion film on the innersurface of the glass tube” may include “the composition of the diffusionfilm includes calcium carbonate, halogen calcium phosphate and aluminumoxide, or any combination thereof,” and may further include “thickenerand a ceramic activated carbon; the diffusion film may be a sheetcovering the LED light source.”

As an example, the feature “coating the reflective film on the innersurface of the glass tube” may include “the LED light sources aredisposed above the reflective film, within an opening in the reflectivefilm or beside the reflective film.”

As an example, the feature “the LED light source being provided with thelead frame” may include “the lead frame has a recess for receive an LEDchip, the recess is enclosed by first sidewalls and second sidewallswith the first sidewalls being lower than the second sidewalls, whereinthe first sidewalls are arranged to locate along a length direction ofthe glass tube while the second sidewalls are arranged to locate along awidth direction of the glass tube.”

As an example, the feature “utilizing the circuit board assembly toconnect the LED light strip and the power supply” may include “thecircuit board assembly has a long circuit sheet and a short circuitboard that are adhered to each other with the short circuit board beingadjacent to the side edge of the long circuit sheet; the short circuitboard is provided with a power supply module to form the power supply;the short circuit board is stiffer than the long circuit sheet.”

According to the disclosed embodiments of the rectifying circuit in thepower supply module, there may be a signal rectifying circuit, or dualrectifying circuit. First and second rectifying circuits of the dualrectifying circuit are respectively coupled to the two end caps disposedon two ends of the LED tube lamp. The single rectifying circuit isapplicable to the drive architecture of signal-end power supply, and thedual rectifying circuit is applicable to the drive architecture ofdual-end power supply. Furthermore, the LED tube lamp having at leastone rectifying circuit is applicable to the drive architecture of lowfrequency AC signal, high frequency AC signal or DC signal.

The single rectifying circuit may be a half-wave rectifier circuit orfull-wave rectifying circuit. The dual rectifying circuit may comprisetwo half-wave rectifier circuits, two full-wave rectifying circuits orone half-wave rectifier circuit and one full-wave rectifying circuit.

According to the disclosed embodiments of the pin in the power supplymodule, there may be two pins in single end (the other end has no pin),two pins in corresponding end of two ends, or four pins in correspondingend of two ends. The embodiments of two pins in single end two pins incorresponding end of two ends are applicable to signal rectifyingcircuit design of the of the rectifying circuit. The embodiments of fourpins in corresponding end of two ends is applicable to dual rectifyingcircuit design of the of the rectifying circuit, and the externaldriving signal can be received by two pins in only one end or in twoends.

According to the disclosed embodiments of the filtering circuit of thepower supply module, there may be a single capacitor, or π filtercircuit. The filtering circuit filters the high frequency component ofthe rectified signal for providing a DC signal with a low ripple voltageas the filtered signal. The filtering circuit may also further comprisethe LC filtering circuit having a high impedance for a specificfrequency for conforming to current limitations in specific frequenciesof the UL standard. Moreover, the filtering circuit according to someembodiments further comprises a filtering unit coupled between arectifying circuit and the pin(s) for reducing the EMI.

A protection circuit may be additionally added to protect the LEDmodule. The protection circuit detects the current and/or the voltage ofthe LED module to determine whether to enable corresponding over currentand/or over voltage protection.

According to the disclosed embodiments of the filament-simulatingcircuit of the power supply module, there may be a single set of aparallel-connected capacitor and resistor, two serially connected sets,each having a parallel-connected capacitor and resistor, or a negativetemperature coefficient circuit. The filament-simulating circuit isapplicable to program-start ballast for avoiding the program-startballast determining the filament abnormally, and so the compatibility ofthe LED tube lamp with program-start ballast is enhanced. Furthermore,the filament-simulating circuit almost does not affect thecompatibilities for other ballasts, e.g., instant-start and rapid-startballasts.

The above-mentioned features of the present disclosure can beaccomplished in any combination to improve the LED tube lamp, and theabove embodiments are described by way of example only. The presentinvention is not herein limited, and many variations are possiblewithout departing from the spirit of the present invention and the scopeas defined in the appended claims.

What is claimed is:
 1. An LED tube lamp, comprising: a glass tube; two end caps disposed at two ends of the glass tube, at least one of the end caps having a main body, an actuator configured to move toward and extend away from the glass tube, a micro switch and an electrically conductive pin, wherein the actuator includes a flange extending radially at an intermediary portion of the actuator and wherein the micro switch is configured to be triggered by the actuator being pressed when the electrically conductive pin receives an external driving signal; a power supply module, disposed in at least one end cap and coupled to the electrically conductive pins of the two end caps; and an LED light strip disposed inside the glass tube with at least one LED light source that is mounted on the LED light strip and electrically connected with the power supply module through the LED light strip; wherein, the glass tube includes a diffusion film to allow the light emitted from the least one light source of the LED tube lamp to pass through the diffusion film and the glass tube surface in sequence; and the micro switch when triggered completes a circuit between the electrically conductive pin and the power supply module.
 2. The LED tube lamp of claim 1, wherein the diffusion film is in the form of a coating layer covering the inner surface of the glass tube.
 3. The LED tube lamp of claim 1, wherein the diffusion film is in the form of a coating layer covering a surface of the least one light source inside the glass tube.
 4. The LED tube lamp of claim 1, wherein the diffusion film is in the form of an optical diffusion coating, which is composed of any one of calcium carbonate, halogen calcium phosphate strontium phosphate, and aluminum oxide, or any combination thereof.
 5. The LED tube lamp of claim 1, wherein the diffusion film is in the form of a sheet covering the least one light source without touching the light sources.
 6. The LED tube lamp of claim 5, wherein the sheet is a composite made of mixing diffusion particles into polystyrene (PS), polymethyl methacrylate (PMMA), polyethylene terephthalate (PET), and/or polycarbonate (PC), or any combination thereof.
 7. The LED tube lamp of claim 5, wherein the glass tube and the end caps are secured by a thermal conductive silicone gel, and the thermal conductivity of the thermal conductive silicone gel is higher than 0.7 w/mk.
 8. The LED tube lamp of claim 1, wherein the glass tube is covered by a heat shrink sleeve.
 9. The LED tube lamp of claim 1, wherein a thickness of the heat shrink sleeve is an amount in the range of 20 μm to 200 μm.
 10. The LED tube lamp of claim 1, wherein a thickness of the diffusion film is an amount in the range of 20 μm to 30 μm.
 11. The LED tube lamp of claim 1, wherein the diffusion film has a light transmittance of between 92% to 94% with a thickness between 200 μm and 300 μm.
 12. The LED tube lamp of claim 1, wherein the glass tube further includes a reflective film disposed on part of the inner circumferential surface of the glass tube.
 13. The LED tube lamp of claim 12, wherein a ratio of a length of the reflective film disposed on the inner surface of the glass tube extending along the circumferential direction of the glass tube to a circumferential length of the glass tube has a value between 0.3 and 0.5.
 14. The LED tube lamp of claim 1, wherein the power supply module is packaged by a heat shrink sleeve.
 15. The LED tube lamp of claim 1, wherein the power supply module further comprises: a rectifying circuit, coupled to the electrically conductive pins of the two end caps for rectifying the external driving signal to generate a rectified signal; and a filtering circuit, coupled to the rectifying circuit for filtering the rectified signal to generate a filtered signal.
 16. The LED tube lamp of claim 15, wherein the power supply module further comprises an anti-flickering circuit, coupled to the filtering circuit, configured such that a current higher than a particular anti-flickering current flows through the anti-flickering circuit when a peak value of the filtered signal is higher than a minimum conduction voltage of the LED module.
 17. The LED tube lamp of claim 16, wherein the anti-flickering circuit comprises at least one resistor.
 18. The LED tube lamp of claim 15, wherein the rectifying circuit is a full-wave rectifying circuit.
 19. The LED tube lamp of claim 1, wherein the power supply module further comprises an over voltage protection circuit, coupled to a first filtering output terminal and a second output terminal of the filtering circuit to detect the filtered signal for clamping a voltage level of the filtered signal when the voltage level of the filtered signal is higher than a particular over voltage value.
 20. The LED tube lamp of claim 19, wherein the over voltage protection circuit comprises a voltage clamping diode.
 21. The LED tube lamp of claim 1, wherein the actuator includes a shaft extending axially at a lower portion of the actuator and movably connected to a base mounted inside the main body.
 22. The LED tube lamp of claim 21, further comprising a coil spring surrounding the shaft between the flange and the base, wherein the coil spring and the flange are configured to move the actuator to its rest position when the electrically conductive pin is not connected to receive the external driving signal.
 23. The LED tube lamp of claim 1, further comprising a coil spring, wherein the actuator includes a spring retainer and a bulging part protruding from a bottom of the spring retainer, and wherein the coil spring is provided between the spring retainer and a base mounted inside the main body.
 24. The LED tube lamp of claim 23, wherein the micro switch is configured to be actuated by the bulging part at a predetermined actuation point and when the electrically conductive pin receives the external driving signal, the actuator is configured to bring the bulging part to the predetermined actuation point and the micro switch is configured to complete the circuit between the electrically conductive pin and the power supply module.
 25. The LED tube lamp of claim 1, further comprising: a first coil spring provided between a spring retainer included in the actuator and a first end of the micro switch; a second coil spring provided between a second end of the micro switch and a base mounted inside the main body, wherein the first coil spring has a first stiffness and the second coil spring has a second stiffness different from the first stiffness.
 26. The LED tube lamp of claim 25, wherein, the micro switch is configured to be triggered when the first coil spring is compressed to a predetermined actuation point, and the micro switch when triggered completes the circuit between the electrically conductive pin and the power supply module.
 27. The LED tube lamp of claim 25, wherein the first coil spring, the second coil spring, and the flange are configured to move the actuator to its rest position when the conductive pin is not connected to receive the external driving signal.
 28. An LED tube lamp, comprising: a glass tube; two end caps disposed at two ends of the glass tube, at least one of the end caps having a main body, an actuator configured to move toward and extend away from the glass tube, a first contact element, a second contact element, and an electrically conductive pin, wherein the actuator includes a flange extending radially at an intermediary portion of the actuator and wherein the first contact element and the second contact element are configured to be triggered by the actuator being pressed when the electrically conductive pin receives an external driving signal; a power supply module, disposed in at least one end cap and coupled to the electrically conductive pins of the two end caps; and an LED light strip disposed inside the glass tube with at least one LED light source that is mounted on the LED light strip and electrically connected with the power supply module through the LED light strip; wherein, the glass tube includes a diffusion film to allow the light emitted from the least one light source of the LED tube lamp to pass through the diffusion film and the glass tube surface in sequence; and the first contact element is configured to engage the second contact element to complete a circuit between the electrically conductive pin and the power supply module when the first contact element and the second contact element are triggered by the actuator.
 29. The LED tube lamp of claim 28, wherein, the actuator includes a shaft extending axially at a lower portion of the actuator and the first contact element and the second contact element face each other through the shaft.
 30. The LED tube lamp of claim 29, wherein the first contact element is configured to impart a spring-like bias on the shaft and to push the shaft against the second contact element. 